Annual Report 2000

Key Centre for Photovoltaic Engineering

UNSW

The University of New South Wales

Centre for Photovoltaic Engineering Electrical Engineering Building

The University of New South Wales UNSW SYDNEY NSW 2052

AUSTRALIA

Tel +61 2 9385 4018 Fax +61 2 9662 4240 E-mail: pv.admin@unsw.edu.au

http://www.pv.unsw.edu.au

The Key Centre for Photovoltaic Engineering

is established and supported under the Australian Research Council’s Centres Scheme.

Table Of Contents

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EXECUTIVE SUMMARY 1. RESEARCH PROGRAMS Research Project 1.1 with BP Solar • Demonstrate reduced rear surface recombination and significant performance

enhancement for the Buried Contact Solar Cell (BCSC) relative to standard product. • Demonstrate selective silicon growth by metal mediated SPE to contact a p-type substrate

in localized areas, leaving oxidized regions unaffected. • Demonstrate high performance using BP Solar materials and processing carried out

predominantly at BP Solar. • Provide photographic evidence through scanning electron micrographs of achievement of

the new rear surface design. • Publish at least two papers based on this work. Research Project 1.2 with Eurosolare • Demonstrate BCSC processes compatible with screen printing infrastructure at

Eurosolare. • Adapt BCSC technology and fabrication sequence for compatibility with the specific

constraints imposed by Eurosolare substrates. • Demonstrate enhanced device performance from the Eurosolare production line using the

same substrates but with an adapted BCSC process. • Transfer of technology to Eurosolare following successful intellectual property

negotiations. • Publish at least two papers based on this work. Research Project 1.3 with BP Solar Research Project 1.4 with Topsil Research Project 1.5 with Solarex Research Project 2.1 with Pacific Solar

• Successful completion of PhD programs of students involved in the project. • Verification by Pacific Solar of satisfaction with Key Centre contributions to the

programs. • Publication of material.

Research Project 3.1 with Pacific Solar Research Project 3.2 with the International Energy Agency (IEA) 2. EDUCATION AND TRAINING PROGRAMS

New Undergraduate Degree in Photovoltaics and Solar Energy New Master of Engineering Science in Photovoltaics and Solar Energy New High Quality Academic Staff New Students Student Surveys IEAust Accreditation New Photovoltaic Teaching Laboratory General Education Electives Teaching Collaborations Publications

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3. INDUSTRY AND USER COMMUNITY LINKAGES Performance Indicators

• Linkages with solar cell and equipment manufacturers • Linkages with other Institutions • Linkages with other industry organisations and end users • Networks and collaboration with other organisations involved in education • National and International Promotion • Collaborative research projects with all Australian PV manufacturers • IEAust Accreditation • Fortnightly seminar series

4. KEY CENTRE INCOME

Introduction Other ARC Grants Other Commonwealth Government Funds Industry/Private Funds Contracts/Consultancies Host Institution Support Other Income Sources

5. COMMERCIALIZATION & TECHNOLOGY TRANSFER 6. AGREED PERFORMANCE INDICATORS 7. KEY CENTRE EXPENDITURE

Salaries Equipment Accommodation Travel Materials and Consumables Other Expenditure Carry-Forward

8. KEY CENTRE MANAGEMENT Overview Advisory Committee Key Centre Staff Postgraduate Research Students

9. KEY CENTRE ACTIVITY PLAN FOR 2001 Teaching Course Development Commercialisation and Technology Transfer Research Activities Promotion Sustainability Teaching Laboratory Development

ATTACHMENT 1 : 2001 School Operational Plan

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EXECUTIVE SUMMARY

Key Centre Director, Professor Stuart Wenham The year 2000 has been an exciting year for the photovoltaics industry with a record annual growth rate exceeding 40% and corresponding unprecedented levels of expansion in manufacturing capacity. This explosive growth makes for perfect timing for many of the Key Centre activities, particularly for the industry collaborative research projects and for the new educational programs that are helping to alleviate some of the pent-up demand for appropriately trained engineers. In fact, the Key Centre is just experiencing for the first time, the premature departure of undergraduate students from the program, being lured by the photovoltaics industry with offers “too good to refuse”. This explosive growth combined with the many successes of the Key Centre and its activities, provides an even stronger rationale now for the Key Centre than when first established several years ago. This Key Centre Annual Report for the year 2000 has been written to satisfy the reporting responsibilities of the Centre to the Australian Research Council. It should be read in conjunction with the general Key Centre report attached, which has been written for a broader audience with approximately 6,000 copies produced for general distribution. The latter gives broad coverage of the Key Centre’s activities but with less emphasis on the specifics of performance targets and milestones as required in the present report. The following major headings are those

provided in the ARC’s Key Centre Guidelines under the section on reporting responsibilities. The corresponding sub-headings represent the performance measures and expected outcomes that were agreed upon between the ARC and UNSW when establishing the Key Centre for Teaching and Research in Photovoltaic Engineering. In many ways, the end of the highly successful year 2000 has come as a relief for the staff of the Key Centre. The commencement of the new undergraduate engineering degree in Photovoltaics and Solar Energy has been the culmination of several years of planning and development. The necessity for such a program has been well known for several years by the Key Centre staff through interaction with industry and end-users. However, attracting new high quality students into this program has remained an important challenge, culminating in the launching of the new degree during the year 2000 with 41 students enrolling in the first year of the program. Almost all of these students have now successfully completed the first year of their program and are currently preparing for the second year, which will include a range of new courses and project work. The positive feedback from the students has been a real source of encouragement for our hardworking staff, who are particularly highly motivated and enthusiastic as they prepare for 2001. In parallel with the new undergraduate degree, the Key Centre has been developing a new Master of Engineering Science in Photovoltaics and Solar Energy. This program will not commence until 2002, with the year 2001 earmarked for gaining the necessary approvals at UNSW for the official implementation of the program. Various other educational courses on photovoltaics are also planned for 2001 such as general education electives for the broader university community, courses via the internet and 32 lectures to be delivered to 1600 high school students on the topic of “innovation” using photovoltaics as a case study. In terms of longer-term planning, the Key Centre is receiving increasing pressure from industry and its Advisory Committee to also develop and implement a broader educational program in Renewable Energy Engineering that encompasses all the renewable energy technologies and their use as well as complementary technologies such as fuel cells.

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Many of the Key Centre activities during 2000 have again been driven by the long-term aim of making the Centre self-sustaining. This has necessitated the investment of resources in activities that have the potential to generate new and reliable income sources. An important part of this process has been the establishment of the Key Centre as an independent budget until within the UNSW financial system. The progress in this area was described in last year’s Annual Report. This independence, however, has been crucial in terms of facilitating the Key Centre’s plans and preparation for developing new and self-sustaining income sources such as through the implementation of the new educational programs at undergraduate and postgraduate level. This has placed particular importance on the Key Centre being able to demonstrate its effectiveness in attracting talented new undergraduate students as well as additional postgraduate research students. The challenge to attract high quality staff has traditionally been an area in which the Key Centre has excelled, aided by the perceived international leadership of the Centre in silicon solar cell research that has made UNSW an attractive location for top quality researchers. During the year 2000, the Key Centre managed to attract back to UNSW a former ARC Postdoctoral Fellow, Dr. Alistair Sproul, who has been working in industry in recent years. Dr. Sproul is a particularly important appointment due to his caliber of teaching that complements his well demonstrated research capabilities. Dr.

Sproul’s teaching interests span well beyond the photovoltaic area and encompass courses such as biomass and other renewable energy technologies. Although the Key Centre has never had a problem appointing top quality staff, the challenge to retain existing staff may become more difficult due to the targeting of our staff by overseas institutions wanting to duplicate our teaching and research activities. During the last 12 months, overseas institutions and companies have been offering academic staff salaries as high as triple those able to be paid at UNSW. Fortunately, we have not as yet lost any academic staff due to these offers. In the research area, the Key Centre continues to perform well with additional technology transfers having taken place during the year 2000 with at least one more planned for 2001. Importantly, these industry collaborative research projects have demonstrated their ability to be self-funding. With the rapid growth in the industry and massive expansion in manufacturing capacity taking place, there appears to be increasing demand particularly from manufacturers wishing to establish collaborative research projects with the Key Centre. As a result, two new projects have been recently negotiated and established, one with a Danish company, Topsil, which is a wafer manufacturer for the integrated circuits industry. The challenge for the Key Centre does not lie with trying to attract interest from industry, but rather to have sufficient staff to negotiate and manage the projects.

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1. RESEARCH PROGRAMS The following will document progress towards targets in the various collaborative research projects with industry. As requested, the work will be reported in conjunction with the original specific performance measures and outcomes identified in the original application and reproduced here in italics. Research Project 1.1 with BP Solar An overview of this project work including a list of staff and students involved is documented in the accompanying general Key Centre report. As was foreshadowed 12 months ago, this project is nearing completion with all the performance targets for the devices having been achieved in the laboratory. The technology transfer of this work and corresponding know-how was completed in early 2000 by Linda Koschier, one of the PhD students working on the project. The transfer of the know-how took place in the laboratory at BP in the UK with the expectation that in several years, these improvements will be implemented onto BP's large scale production facility. To aid the on-going collaboration between BP and the Key Centre in this area, BP Solar offered to employ Linda Koschier when she completed her PhD in early 2000. The only further development in this work during the year 2000 has been to simplify the techniques used for implementing the improvements, with a corresponding patent having been filed on the latest innovative aspects of the approach in April, 2000. These developments have not led to further improvements in the device efficiencies but rather have led to significant simplification of the processes needed for their fabrication. The following reports on progress against the performance measures and expected outcomes documented in the original Key Centre application: • Demonstrate reduced rear surface

recombination and significant performance enhancement for the Buried Contact Solar Cell (BCSC) relative to standard product.

This milestone was successfully achieved during 1999 and has been previously reported and widely published.

• Demonstrate selective silicon growth by metal mediated SPE to contact a p-type substrate in localized areas, leaving oxidized regions unaffected.

This was also achieved during 1999 with scanning electron micrographs produced to verify the successful implementation of the described approaches. The ability to carry out the selective silicon growth through openings in the rear surface silicon dioxide layer has been successfully demonstrated without causing damage to the remaining regions of silicon dioxide that provide rear surface passivation for the wafer. Two new publications on this work have been published during 2000. • Demonstrate high performance using BP

Solar materials and processing carried out predominantly at BP Solar.

Significant improvement in performance has been demonstrated using the new techniques when using BP supplied materials such as the silicon substrates. Although the technology transfer to BP Solar has taken place and appropriate equipment has been commissioned to carry out the processes, the devices fabricated at BP Solar have not as yet matched the performance of those produced in the laboratories at the Key Centre or those co-fabricated between the two locations. During 2001, this work will proceed under the control of BP Solar but with the Key Centre providing technical advice and assistance when required. If requested, the Key Centre will co-process aspects of the devices to help identify why lower performance is being achieved in the BP laboratories. • Provide photographic evidence through

scanning electron micrographs of achievement of the new rear surface design.

This has been successfully done with the corresponding scanning electron micrographs having been included in published papers and also in the PhD thesis by L. M. Koschier “Multijunction and novel silicon photovoltaic device structures”. Various approaches for creating the openings in the rear oxide layer to facilitate the subsequent solid phase epitaxial growth of silicon onto the exposed wafer surface have been successfully demonstrated. These have included both mechanical and chemical approaches in addition to the use of laser ablation.

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• Publish at least two papers based on this work.

Much of this work was published during 1999 although two new manuscripts have been published during 2000. These are: (i) L.M. Koschier and S.R. Wenham, “A

New Approach for Forming Device Contacts with Improved Surface Passivation”, paper presented at 28th

IEEE Photovoltaic Specialists Conference, Anchorage, Alaska, September, 2000;

(ii) Koschier, L.M., Wenham, S.R., “Improved Voc using Metal Mediated Epitaxial Growth in Thyristor Structure Solar Cells”, Progress in Photovoltaics, Vol. 8, No. 5, September, 2000, pp489-501.

A large amount of work has been described in these two publications, broader than that funded by BP Solar in this project. For example, it encompasses work on thyristor devices that was funded by an ARC large grant. Research Project 1.2 with Eurosolare The work on this project has progressed more rapidly than originally anticipated, aided significantly by being awarded a SPIRT grant by the ARC. The SPIRT grant has also enabled the original project aims to be expanded. A broad description of this project is provided in the accompanying general Key Centre report. The following describes progress against the specific performance measures and expected outcomes as documented in the original Key Centre application. • Demonstrate BCSC processes compatible

with screen printing infrastructure at Eurosolare.

Although much of the developmental work in this area was conducted at the Key Centre, the ultimate success of the work in terms of demonstrating compatibility with the infrastructure at Eurosolare has required frequent visits of UNSW staff and students to Eurosolare. Reciprocal visits by Eurosolare technicians and researchers to the Key Centre to facilitate training and subsequent process evaluation at Eurosolare have also taken place. The most critical process in the new BCSC

technology has been the deposition and use of the titanium dioxide antireflection coating. Although a similar deposition system has been established at the Key Centre, differences in the high throughput production equipment at Eurosolare has nevertheless necessitated much of the developmental and demonstration work to be carried out at Eurosolare. To this end, two of the Key Centre’s PhD students, Bryce Richards and Keith McIntosh, have spent considerable periods of time at Eurosolare specifically working on this part of the process. This antireflection coating is quite critical because it not only provides the required good optical performance for the devices through low reflection, but also must act as a plating mask against the electrolessly deposited metals and also must be able to be deposited so as to selectively protect the wafer top surface while leaving the grooves exposed for subsequent processing. Adapting the processing parameters and conditions to achieve these aims has been successfully accomplished. The other critical body of work in relation to the compatibility of this part of the production facility of Eurosolare to the BCSC technology has been in relation to achieving good surface passivation of the emitter, which is essential for the high performance BCSC devices. An important breakthrough has taken place in this area of work through the demonstration of very well passivated emitter surfaces in conjunction with the titanium dioxide layers deposited at Eurosolare. This breakthrough has been aided through the demonstrated ability to form a thin passivating oxide through the titanium dioxide layer directly at the interface between the silicon and the titanium dioxide. This particular portion of the work is considered particularly important and has been recently published (B. S. Richards, J E. Cotter, C B. Honsberg, and S R. Wenham, “Novel Uses Of TiO2 In Crystalline Silicon Solar Cells”, 28th IEEE Photovoltaic Specialists Conference, Alaska, September 2000). The compatibility of the screen printing processes for the application of the rear metal contact has been previously successfully demonstrated, together with the plasma etching process for edge junction isolation. The chemical etching/texturing processes used on the Eurosolare production line have also now been demonstrated to be compatible with the BCSC technology. This part of the work was easily accomplished through part processing of devices at Eurosolare which

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were then sent to the Key Centre where the remainder of the BCSC processing was successfully carried out. The remaining process from the standard Eurosolare production facility that needs adaption for the new BCSC processes is the phosphorus diffusion. This work has been temporarily delayed due to the change in production processes taking place in this area on the standard production facility of Eurosolare. Eurosolare has recently applied for patent protection for a new type of furnace in which to carry out the phosphorus diffusion. It is therefore necessary to wait until this equipment is properly commissioned and available for this work before compatibility can be demonstrated. The main challenge will be to achieve adequate diffusion in the grooves as required for the BCSC process. This work is expected to resume midway through 2001. • Adapt BCSC technology and fabrication

sequence for compatibility with the specific constraints imposed by Eurosolare substrates.

The main constraints imposed by Eurosolare substrates relate to limitations imposed on high temperature thermal treatments which if excessive cause degradation of the substrates. To this extent, the BCSC technology has been significantly adapted to alleviate the need for all the lengthy high temperature processes. This has required some compromises in design but with the adapted technology appearing to have strengths in terms of simplicity, cost and device performance. The main compromise has been the elimination of the high temperature groove diffusion which has been demonstrated with high quality substrates to give as much as 70 mV improvement in open circuit voltage. However, the Eurosolare substrates are of significantly lower quality making it impossible to achieve this 70 mV improvement in open circuit voltage regardless of the presence of the groove diffusion. The elimination of the groove diffusion therefore has minimal impact on the device voltages and yet provides for much simpler overall processing and avoids the damaging lengthy high temperature processes that would otherwise degrade the substrates. The other area in which the BCSC technology has needed adaptation to suit the Eurosolare substrates has been in the area of the use of antireflection coatings to reduce surface

reflection. The original BCSC technology developed at UNSW did not use an antireflection coating, but rather relied on surface texturing to minimize reflection. Eurosolare substrates cannot be textured in the same way and have therefore necessitated the inclusion of an antireflection coating in the process. This work has involved the implementation of the titanium dioxide antireflection coating and has already been described in detail above. Again, this outcome has been successfully achieved. • Demonstrate enhanced device

performance from the Eurosolare production line using the same substrates but with an adapted BCSC process.

To date, the high performance devices successfully produced in this project have only used partial processing on the Eurosolare production line. The aim by the end of the project will be to demonstrate the entire adapted BCSC process using only the Eurosolare production line. This work is targeted for completion at the end of 2002. As progress towards this target, the above description of the processes that have already been successfully adapted and implemented on the Eurosolare production line is evidence of the progress that has been taking place during 2000. • Transfer of technology to Eurosolare

following successful intellectual property negotiations.

As is documented in the accompanying general Key Centre report, Eurosolare have proceeded to license the BCSC technology from UNSW in anticipation of the successful completion of this project. A formal technology transfer process has taken place with Eurosolare technicians being initially trained within the UNSW laboratories leading to their fabrication of devices with efficiencies above 17%. This is the performance target set to demonstrate the successful transfer of the technology. However, the technology transfer process is on-going due to the collaborative research project between Eurosolare and the Key Centre which continues to show improvements in the technology. During the year 2000, Associate Professor C.B. Honsberg and Professor S.R. Wenham both visited the Eurosolare production facility as part of the technology transfer process. In addition, as indicated above, two PhD students from the Key Centre spent a prolonged period of time

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at Eurosolare also transferring the latest technological achievements derived from the project. In February, 2001, Eurosolare research manager, Dr. Francesca Ferrazza and a Eurosolare technician, Rocco Nacu, will again both visit the Key Centre laboratories for additional technology transfer of the latest developments. • Publish at least two papers on this work There have been ten refereed publications arising from this work although approximately half of them are quite broad, encompassing work that is additional to that conducted as part of this collaborative research project with the Italian company Eurolare. Of particular importance is the patent that has been awarded in relation to this novel work, which testifies to its originality. The relevant publications are:

1. Vogl, B., Pritchard, S.C., Gross, M., Honsberg, C.B., Cotter, J.E., and Wenham, S.R., “The Use of Silicon Nitride in Buried Contact Solar Cells”, Mater Sol Cells v 66 n 1-4 Feb 2001 p 17-25

2. Wenham, S.R., Honsberg, C.B., Cotter, J.E., Largent, R., Aberle, A.G, and Green, M.A., “Australian Education and Research Opportunities Arising Through Rapid Growth in the Photovoltaic Industry”, Solar Energy Materials and Solar Cells, v 67 n 1-4 Mar 2001. p 647-654

3. Honsberg, C.B., Cotter, J.E., Richards B.S., Pritchard, S.C., Wenham, S.R., “Design Strategies for Commercial Solar Cells Using the Buried Contact Technology”, IEEE Transaction on Electron Devices, Vol 46 no. 10, pp1984-1992, (1999).

4. Cotter, J.E., Mehrvarz, H.R., Honsberg, C.B. and Wenham, S.R., “Combined Emitter and Groove Diffusion in Buried Contact Solar Cells”, accepted for 16th EPVSC, May 2000.

5. Wenham, S.R., Honsberg, C.B., Cotter, J.E, Largent, R., Aberle, A.G.,

Spooner, T., and Green, M.A. “Opportunities arising through the rapid growth of the photovoltaic industry”, 11th Photovoltaic and Solar Energy Conference, Japan, 1999.

6. Cotter, J.E., Richards B.S., Ferrazza, F., Honsberg, C.B., Leong, T.W., Mehrvarz, H.R., Naik, G.A. and Wenham, S.R., “Design Of A Simplified Emitter Structure For Buried Contact Solar Cells”, 2nd World Photovoltaics Specialists Conference, pp. 1511-1513 (1998).

7. Richards B.S., Cotter, J.E., Ferrazza, F., Honsberg, C.B. and Wenham, S.R., “Lowering the Cost of Commercial Silicon Solar Cells”, Proc. of Environmental Engineering Research Event, Dec 1998, p.303-307.

8. Wenham, S.R., Honsberg, C.B., Edmiston, S., Koschier, L., Fung, A., and Green, M.A., “Simplified Buried Contact Solar Cell Process”, 25th IEEE Photovoltaic Specialist Conference, Washington, DC, pp. 13-17, (1996).

9. B. Vogl, A. M. Slade, C. B. Honsberg, J. Cotter and S. R. Wenham, "Inclusion of Dielectric Films for Surface Passivation of Buried Contact Solar Cells", paper presented at 28th IEEE Photovoltaic Specialists Conference, Anchorage, Alaska, September, 2000.

10. Bryce S. Richards, Jeffrey E. Cotter, Christiana B. Honsberg, and Stuart R. Wenham, (2000), “Novel Uses Of TiO2 In Crystalline Silicon Solar Cells”, 28th IEEE Photovoltaic Specialists Conference, Alaska, September 2000.

PATENT arising from work

11. Wenham, S. R., Honsberg, C.B. and Green, M.A., “Metalization of Buried Contact Solar Cells”, Australian Patent issued 1 April 1999. Patent number 699936.

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Research Project 1.3 with BP Solar In late 2000, BP Solar expressed an interest in establishing a new collaborative research project and indicated their willingness to contribute $50,000 per year. These funds are inadequate to employ a full-time researcher on the project as well as cover the running costs for the project. The funds are therefore earmarked for a scholarship for a PhD student who has been selected by BP Solar. The student awarded the scholarship completed electrical engineering last year and graduated with first class honours. His name is Peter Cousins and his work will aim at generating new ideas for cell design that can build on the previous developments in Project 1.1 above and with the BCSC technology in general. In many ways, this project, although separately negotiated, could be seen as an extension of the original Project 1.1. If the quality of work in this project is sufficiently high and the ideas sufficiently important, ARC SPIRT funding will be applied for. Research Project 1.4 with Topsil This is a new collaborative research project which has just commenced with the Danish company, Topsil. Topsil has been a producer of silicon wafers for many years, focussing primarily on floatzone technology which has always been recognized as being too expensive for use by the photovoltaic industry. However, recent new insights into the limitations associated with existing commercial cell technologies have revealed that boron/oxygen defects in the standard Czochralski (CZ) material cause serious degradation of the substrate minority carrier lifetimes relative to floatzone material where the oxygen concentration is much lower. This has generated an interest by Topsil in adapting their floatzoning processes to produce lower cost material that is still capable of achieving substantially higher device efficiencies in commercial production than CZ counterparts. The collaborative research project will involve Topsil producing pilot material for evaluation at the Key Centre. Key Centre staff will characterize and evaluate the material and apply existing cell technologies for device demonstration. The feedback provided to Topsil will enable them to refine their floatzoning processes to gain greatest benefit from the cost/performance trade-off.

Work in this project has already commenced with Topsil sponsoring a student project at UNSW relating to making the solar cells for the University’s solar car. The support for this project has been jointly provided by the Faculty of Engineering and Topsil with the students having already fabricated several thousand cells using the Topsil pilot floatzone material and using the standard BCSC technology. Efficiencies above 19% have been achieved, giving a significant performance advantage over the equivalent CZ produced devices which are 10% lower in performance. The staff involved in this project are Associate Professor C.B. Honsberg, Dr. J. Cotter and Professor S.R. Wenham. This project is expected to be suitable for the involvement of at least one PhD student. Research Project 1.5 with Solarex This project has been broadly described in the accompanying general Key Centre report. As was foreshadowed as a possibility in the last Annual Report, the commencement of this project has been delayed due to the merger that has taken place between the major oil companies, BP and Amoco. Solarex has now been incorporated into BP Solar, the company with which we have two other collaborative research projects. This project has therefore been de-emphasized in the short term with future decisions with regard to its funding reliant on internal decisions within the newly formed BP Solar regarding technology priorities and objectives. Research Project 2.1 with Pacific Solar A broad description of this project work is provided in the accompanying general Key Centre report. In the last annual report, a measure of the success and effectiveness of this project and the progress of Pacific Solar was indicated by the establishment of the pilot production facility six months ahead of schedule. The work in this project, although not specifically targeted to finish at any particular date, will reduce in its importance as the technology nears the production phase. An important measure of the success of this work has been the successful establishment of the Pacific Solar Pilot Production line for fabricating photovoltaic modules six months ahead of schedule. Another important indicator of the success of this work has been the decision of the Italian company,

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Eurosolare, to invest heavily in the future of Pacific Solar. This is the same company with whom the Key Centre has the collaborative research Project 1.2 described above. Eurosolare has evaluated this new generation of thin film technology and its potential and has concluded that this is the way commercial technology must head in the long term for photovoltaics to realize their full potential. Progress against the specific performance measures and expected outcomes listed in the original Key Centre application are as follows: • Successful completion of PhD programs

of students involved in the project. Of the two PhD students listed in last year’s Annual Report, Oliver Nast has now completed and been awarded his PhD. The second student, Nicholas Shaw, is receiving a scholarship from Pacific Solar with the 3 year duration of the scholarship expiring during 2002. A third PhD student, Bradley O’Mara, has also been engaged in collaborative research work with Pacific Solar and has now completed his experimental work. He has completed writing a draft version of his PhD thesis and is expected to receive his PhD midway through 2001. • Verification by Pacific Solar of

satisfaction with Key Centre contributions to the programs.

Pacific Solar management has repeatedly indicated its satisfaction with the contributions made by the Key Centre and its staff to the Pacific Solar activities. In fact, the Pacific Solar management has indicated that even though the usefulness of the present project is expected to diminish over the next year or so, it wishes to maintain an on-going and strong collaboration with the Key Centre and its staff. Further work programs are therefore likely to be negotiated in the future. • Publication of material. There have been 12 reports written in conjunction with this project during 2000. These are: A.B. Sproul, TDG Device Characterisation Progress Report, Volume 6, February 2000, pp19-22. A.B. Sproul, TDG Device Characterisation Progress Report, Volume 6, March 2000, pp31-38. T. Puzzer and R. Bardos, TDG Device Characterisation Progress Report, Volume 6,

March 2000, pp39-42. A.B. Sproul, TDG Device Characterisation Progress Report, Volume 6, April 2000, pp83-86. A.B. Sproul, TDG Device Characterisation Progress Report, Volume 6, May 2000, pp145-152. A. B. Sproul, TDG Device Characterisation Progress Report, Volume 6, Number 6, June 2000. A. B. Sproul, TDG Device Characterisation Progress Report, Volume 6, Number 7, July 2000. A. B. Sproul, TDG Device Characterisation Progress Report, Volume 6, August 2000, pp227-230. A. B. Sproul, TDG Device Characterisation Progress Report, Volume 6, September 2000, pp249-252. A. B. Sproul, TDG Device Characterisation Progress Report, Volume 6, October, 2000. A. B. Sproul, TDG Device Characterisation Progress Report, Volume 6, Number 11, November, 2000. A. B. Sproul, TDG Device Characterisation Progress Report, Volume 6, December, 2000, pp305-310. There have also been two patents applied for during this project that include the Key Centre director as a co-inventor. Furthermore, the PhD theses of the students involved in the collaborative work with Pacific Solar also constitute publication of material. A progress report has also been written for this project as a result of it attracting funding under the ARC SPIRT scheme. Research Project 3.1 with Pacific Solar The work in this project has been briefly described in the accompanying general Key Centre report.

Figure: Pacific Solar Roof-top system

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It has focused on the provision of experience, advice, facilities and equipment from the Key Centre to assist Pacific Solar with the development of its new inverter shown below.

This work has taken place more like a consultancy arrangement whereby the Key Centre has made available its staff and facilities to be called upon by Pacific Solar as the need arises. This has been another highly successful collaborative project with Pacific Solar who has brought its new inverter design onto the market as a commercial product during 2000. The figure above shows a system installed by Pacific Solar and is typical of many such systems installed throughout New South Wales in recent months by Pacific Solar. The figure below shows a photograph from the same installation highlighting the black box which contains the sophisticated inverter circuitry that interfaces the solar panel to the electricity grid. These inverters have in-built intelligence to enable self-diagnosis, monitoring and communication.

Figure: The black boxes are the Pacific Solar Inverters commercialised during 2000. One is used for each photovoltaic module

Research Project 3.2 with the International Energy Agency (IEA) UNSW is a member of the Australian Photovoltaic Power Systems (PVPS) Consortium for the International Energy Agency PVPS program, one of the collaborative R & D agreements established within the IEA. UNSW responsibilities are shared between Solarch and the Key Centre, with the involved staff including Muriel Watt, Hugh Outhred (Advisory Committee member)

and Ted Spooner (adjunct member of the Key Centre). The overall program is headed by an Executive Committee composed of one representative from each participating country, while the management of individual research projects (Tasks) is the responsibility of Operating Agents. The Australian consortium is involved with several program tasks, including Task 1 Exchange and dissemination of information on PVPS Task 3 Use of PVPS in stand-alone and island applications Task 5 Grid interconnection of building integrated and other dispersed PVPS Task 7 PVPS in the built environment Task 9 Technical co-operation for PV market deployment The consortium meets four times a year and a wide range of topical PV information is distributed and discussed. PV Centre staff have been particularly involved in the activities of Tasks 1, 5 and 7. For PVPS Task 1 the Consortium produces an annual report on Australian activities, which was written by Muriel Watt in 2000. This is used with reports from other IEA PVPS member countries to produce an international report. Task 1 also produces quarterly newsletters, which feature new projects. Australian projects have been featured in several issues. Centre staff have the opportunity to contribute to all the material produced by the projects in which the Australian Consortium is involved and also have access to all output. This provides valuable links to international PV applications and ensures that an Australian perspective is always taken into account in recommendations for international guidelines, standards or activities. The Centre will also have access to educational material on PV in Buildings which is being produced by PVPS Task 7. In March 2000, Martin Green, Muriel Watt, Hugh Outhred and Ted Spooner participated in an international conference entitled “Renewable Energy for the New Millennium”, which was co-organised by the IEA PVPS.

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2. EDUCATION AND TRAINING PROGRAMS

A detailed overview of the teaching activities and programs developed and offered by the Key Centre is included in the attached general Key Centre report. The following sub-headings each represent a performance measure or expected outcome listed in the original Key Centre proposal that was accepted by the ARC. A sub-section on “publications” in the teaching area is also provided, New Undergraduate Degree in Photo-voltaics and Solar Energy The primary new initiative of the Key Centre in the educational area has been to develop and implement a new engineering degree in Photovoltaics and Solar Energy. Much of the development of this program took place in 1999, with the University formally approving the program for commencement in the year 2000. The year 2000 has therefore been an exciting year with 41 students enrolling in the first year of the new program. The students entering the program have not been typical of those entering most of the engineering programs with a much greater proportion of females (approaching 50%). The new program has demonstrated its appeal to the top performing students at secondary level as shown by the UAI distribution in the figure below which has a median UAI in the vicinity of 95 for students entering the program

through the UAC system. This ranks the program amongst the most prestigious ones offered by UNSW when ranked on the basis of median UAI scores. Perhaps more importantly, the students appear particularly motivated in their studies and demonstrate a commitment and passion for photovoltaics and solar energy. New Master of Engineering Science in Photovoltaics and Solar Energy A new Master of Engineering Science program has been developed in parallel with the new undergraduate degree program with several of the courses ready for implementation. The formal approval of this new MEngSci in Photovoltaics and Solar Energy is expected during 2001 following approval at the School, Faculty, Academic Board and University Council levels. The first enrolments in this program are anticipated in 2002. New High Quality Academic Staff In last year’s Annual Report, it was reported that the Key Centre had attracted two new high quality academic staff members, namely Dr. Armin Aberle from Germany and Dr. Jeff Cotter from the United States. During the year 2000, the Key Centre also managed to attract Dr. Alistair Sproul, a former recipient of an ARC Postdoctoral Fellowship prior to working for several years in industry with the

Histogram of Student UAI for new BE Degree in Photovoltaics and Solar Energy

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12

9

5

1 1

0

24

6

8

10

12

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97-100 94-97 91-94 88-91 85-88 82-85

UAI- University Admissions Index, numbers

Num

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f stu

dent

s en

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company Pacific Solar Pty. Ltd. In addition to his strong research performance, Dr. Sproul has an excellent teaching record that will be of great benefit to the Key Centre in its development and implementation of the new undergraduate and postgraduate degrees. The Centre now has six full time academic staff members, twice the number it had when originally applying for the establishment of the Key Centre. New Students In last year’s Annual Report, it was revealed that the Key Centre enrolled 41 students into the first year of the program compared to the University quota of 30. The increased enrolments came about as a result of the extraordinarily high acceptance rate of 97% (figures supplied by the Dean’s office) of the offers sent out by the University’s Admissions Section. Apparently 60% acceptance rate is more normal for other programs. As a consequence, the offers sent out by UNSW the following year were reduced somewhat but with the number of acceptances and hence enrolments still exceeding the upper limit of the target range of 25-35 students listed as a performance measure in the original Key Centre proposal. Again, the median UAI appears to be well above 90. With respect to attracting new PhD enrolments, it was reported 12 months ago that the two new academic staff members, Dr. Aberle and Dr. Cotter, had collectively attracted seven new postgraduate research students. The addition of Dr. Sproul to the academic staff will now further increase our capacity to take on additional PhD students. For example, three new PhD students are commencing at the beginning of 2001. Student Surveys The Key Centre has implemented the policy of surveying every course taught within the Centre at least once in every three times the course is offered. The highest priority is given to surveying new courses to aid in the process of refining the course content and the way it is presented. The two new courses offered in semester 1, 2000 were therefore surveyed to gain feedback from students. These included the first year course, Introduction to Photovoltaics, Solar Energy and Computing, and the second year project, Photovoltaics and Solar Energy. Both were judged by the students to be well above average both in terms of the quality of

teaching and the quality of the material taught. These surveys will continue to be used regularly, particularly with the new courses. A survey was also conducted during 2000 of a 1st year course being taught by one of the other Engineering schools that was causing problems for our students. The feedback from this survey was passed on to the relevant school with the outcome that special tutorial classes were organised to provide for the students’ needs. IEAust Accreditation One of the expected outcomes listed under “Teaching” in the original Key Centre proposal was to gain IEAust accreditation. This is not possible prior to the year 2005 due to the rules for gaining accreditation. Apparently, full accreditation can only be applied for once students have completed the program and worked in industry for at least one year. Nevertheless, the new degree has been developed directly in line with the formulated policy and guidelines for achieving IEAust accreditation, conformance to which was a requirement for gaining approval within the UNSW system. Two Key Centre academics, Professor S.R. Wenham and Dr. J. Cotter, are also members of the IEAust accreditation committee for engineering at UNSW. This accreditation committee meets fortnightly as UNSW prepares the necessary material in preparation for the accreditation process to take place in September, 2001. Even though the Key Centre cannot gain full accreditation before 2005, our academics in attendance are ensuring that appropriate paperwork and material is developed now to facilitate preliminary assessment by the IEAust accreditation committee. New Photovoltaic Teaching Laboratory UNSW has provided the Key Centre with two rooms in the Electrical Engineering Building (416 and 417) for the development of the Centre’s Photovoltaic Teaching Laboratory. Work on this laboratory commenced during 2000 with a range of experiments and corresponding hardware being designed. This laboratory is expected to be partially functional by May 2000, ready for the undergraduate students to conduct various laboratory exercises and experiments for their new courses. There will be, in general, seven sets of hardware for each experiment, one for

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demonstration purposes and six for use by student groups. Room 416 will act as an extension to the main laboratory facilities in room 417 and will also hold many of the teaching computers. Part of the roof space on top of the building has also been made available by UNSW for students in this program, particularly to allow access to the rooftop grid-connected photovoltaic systems being installed for various student experiments. General Education Electives One of the earliest aims of the teaching program was to develop and teach two new general education electives relating to the photovoltaics and solar energy area. These courses facilitate the education of the broader University community in this new and rapidly growing industry. The target date was to complete the development of both courses by the end of 1999. This was achieved ahead of schedule with both electives being offered during the year 2000. One elective provides a broad education encompassing all of the renewable energy technologies. The other focuses on solar cars as a high profile application of photovoltaic technology. This course provides an interesting way to introduce students to the potential of this solar technology but in a way that links it to a range of other disciplines by virtue of the fact that the solar car project at UNSW requires mechanical engineers for the mechanics, electronics engineers for the control and interface circuitry, telecommunications engineers for the telemetry system, computer engineers for the monitoring and the computer control, chemical engineers for the battery technology, marketing people, financial advisors, media officers, etc.. The solar car elective in particular is proving to be quite popular amongst students from other disciplines. Teaching Collaborations The Key Centre has been approached by several other institutions both nationally and internationally wishing to collaborate with the development and implementation of educational programs. One such collaboration is with Murdoch University in Perth, WA where Key Centre academics have assisted with the co-ordination and implementation of a somewhat similar undergraduate degree in Renewable Energy Engineering. The Key Centre has made available some of its courses for the students

at Murdoch University. Another collaboration has been established with the Georgia Institute of Technology in the United States. In this case, the model likely to be implemented will be one where Key Centre staff assist the Georgia Institute of Technology to set up necessary core teaching in photovoltaics and solar energy for the first and second years of a new program. In the third year, it is anticipated that these students will then travel to UNSW for an intensive 12 months of teaching in photovoltaics and solar energy. At the completion of the third year of the program, the students will then return to the Georgia Institute of Technology to complete their final year of study. To aid in this collaboration, Associate Professor C.B. Honsberg has made two trips to the Georgia Institute of Technology, the second of which will be for several months to help establish appropriate teaching of core material in the early years of the proposed new program. The details of this new program should be formulated during 2001. A third collaboration has been negotiated with Loughborough University in the United Kingdom. This collaboration will focus primarily on sharing/swapping teaching resources developed at the respective institutions. For example, the new CDROM “Photovoltaics” developed by Associated Professor C.B. Honsberg and Dr S. Bowden has been made available to the staff at Loughborough University to aid in their teaching. Permission has also been granted (at a negotiated cost) for the staff at Loughborough University to include the material from this CDROM on their own much broader CDROM to provide coverage of the photovoltaics area. In general, sales of teaching resources such as books and multimedia CDROM’s have been increasing each year as shall be noted from the financial statement. Various other international teaching collaborations are currently being negotiated such as with the Oregon Renewable Energy Centre at the Oregon Institute of Technology in the United States. Within Australia, an excellent mechanism for facilitating collaboration has been established indirectly as a result of the collaboration with Murdoch University. Financial support from the Australian CRC for Renewable Energy (ACRE) to support the development of new courses for the Murdoch University and UNSW programs has also facilitated

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capitalizing on expertise available at other institutions such as through Ralph Simms from Massey University in New Zealand and Keith Lovegrove from the Australian National University. With the addition of Curtin University (also in Perth), this provides a six way collaboration involving five universities plus ACRE. Perhaps more importantly, this collaboration is providing access to valuable expertise and material that would otherwise be costly to acquire. Of these institutions, only UNSW and Murdoch University are implementing undergraduate engineering programs, with the remainder developing courses being offered at the postgraduate level. The Centre for Photovoltaic Engineering has also establish an ongoing collaboration with several institutions in Thailand. The Centre hosted three Thai university academics for eight weeks as part of the Thailand-Australia Science and Engineering Assistance Project sponsored by the Kingdom of Thailand Ministry of University Affairs and the Australian Agency for International Development. The TASEAP Fellows came from Chaing Mai University and Burupa University, both of which have strong teaching and research interests in photovoltaics and renewable energy. The aim of the fellowship programs was to expose Fellows to the teaching and teaching development activities as well as the research activities of the Centre. This was achieved by immersing the Fellows in the day-to-day activities of the Centre including attending lectures in several courses, participation in the internet-based Applied Photovoltaics Short Course, attendance at research meetings and participation in various research and teaching projects. Publications Although there were no specific performance

measures or targets relating to publications in the teaching area, there have in fact been several more such refereed publications during 2000 that further testify to the innovativeness and importance of the teaching activities and educational programs. These include: (i) S.R. Wenham, C.B. Honsberg, J.

Cotter, T. Spooner, M.A.Green, M.D. Silver, R. Largent and L. Cahill, "Australian Initiatives in Photovoltaic Engineering Education", 16th European Photovoltaic Solar Energy Conference, Glascow, April 2000

(ii) S.R. Wenham, H. Outhred, P. Jennings, P. Lee, New Undergraduate Engineering Programs in Renewable Energy, 7th International Symposium on Renewable Energy Education, Oslo, June 2000.

(iii) S.R. Wenham, C.B. Honsberg, J. Cotter, M.A. Green, A.G. Aberle, A. Bruce, M.D. Silver, R. Largent and L. Cahill, “Commencement of World’s First Bachelor of Engineering in Photovoltaics and Solar Energy”, paper presented at 28th IEEE Photovoltaic Specialists Conference, Anchorage, Alaska, September, 2000.

(iv) S.R. Wenham,, C.B. Honsberg, M. Wat, M.A. Green, J. Cotter, R. Largent, M.D. Silver, A.G. Aberle, T. Spooner and L. Cahill, World’s First Bachelor of Engineering in Photovoltaics and Solar Energy, 7th International Symposium on Renewable Energy Education, Oslo, June 2000

(v) S.R. Wenham, C.B. Honsberg, J.E. Cotter, R. Largent, A.G. Aberle and M.A. Green, “Australian Educational and Research Opportunities Arising Through Rapid Growth in the Photovoltaic Industry”, Solar Energy Materials and Solar Cells, vol. 67, pp. 647-654, 2001

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3. INDUSTRY AND USER COMMUNITY LINKAGES

An extensive network of linkages has been established between the Key Centre and manufacturers, other institutions, industry representatives, and other organizations associated with the industry. Important linkages have been established that impact the Key Centre’s teaching activities, collaborative research projects and in general provide liaison and interaction with those involved in the photovoltaics and renewable energy industries Performance Indicators A range of relevant performance indicators were listed in the original Key Centre proposal, the most important relating to the establishment, nurturing and making use of linkages with manufacturers, end-user groups and other institutions. As can be seen from the following, the Key Centre has performed well, with each bulleted heading summarising the relevant performance measure or expected outcome. • Linkages with solar cell and equipment

manufacturers BP Solar (UK, USA): licensee of Key Centre technology and major contributor to both teaching programs and industry collaborative research projects with the Key Centre. David Jordan is a member of the Key Centre Advisory Committee. BP also offers a scholarship at postgraduate level which has been awarded to Peter Cousins and has also indicated its willingness to offer a co-operative scholarship for a student in the new undergraduate engineering degree in Photovoltaics and Solar Energy. Eurosolare (Italy): licensee of Key Centre technology and major contributor to both teaching programs and industry collaborative research projects. Dr. Francesca Ferrazza, the company’s Research Director, is a member of the Key Centre Advisory Committee. Topsil (Denmark): involved in collaborative research project with the Key Centre and has expressed interest in licensing Key Centre technology for manufacturing. Pacific Solar (Australia): offers co-operative scholarships for students enrolled in the new engineering degree in photovoltaics and solar energy. Involved in two collaborative

research projects with the Key Centre and makes major contributions to the teaching programs such as through student visits and provision of material for courses. The managing director, David Hogg, is a member of the Key Centre Advisory Committee. Professor Paul Basore, the company’s deputy research director, is also an adjunct appointment to the Key Centre. NPC Incorporated (Japan, USA, Germany): A close liaison is being established between NPC and the Key Centre. NPC has expressed its intention to develope and manufacture equipment specifically for technology developed at UNSW. The contact person from NPC is Dr Julio Bragnolo. Suntech Power Company Ltd (P. R. China): new company in the Asian region just in the process of planning future manufacturing. One of the company’s senior managers, Dr. Zhengrong Shi, has established a collaboration with the Key Centre to ensure the company’s access to Key Centre technology and consulting expertise. Suntech Power has also offered assistance to the Key Centre in teaching and course development. Techstar (USA): user of UNSW technology for space applications. A close liaison has existed for many years with the contact person, Peter Iles, a recipient of the prestigious William Cherry Award. Global Sustainable Energy Solutions (Australia): Geoff Stapleton is a member of the Key Centre Advisory Committee and is particularly well networked in the industry as a whole therefore providing a large number of indirect linkages for the Key Centre beyond those listed in this report. Photo Watt International (France): Roland Einhaus and Dr. Quang Nam Le have requested an on-going liaison with the Key Centre, particularly for the purpose of providing expertise, training for engineers and possible future access to UNSW technology. Photo Watt has indicated their interest in establishing a collaborative research project in the future. They have also provided access for Key Centre staff to their highly automated production facilities with the option now being explored to use this material in educational courses at UNSW. They have expressed their interest in contributing to the development of the “virtual production line” for the UNSW degree program, provided they then have access to the developments.

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Other manufacturers: The Key Centre has excellent linkages with all the licensees of its technology. The contracts automatically provide the licensees with on-going access to new innovations in UNSW technology and the potential for further training. The Key Centre has licensees in many major countries including the United States, Australia, the UK, Germany, Italy, Spain, India and South Korea. • Linkages with other Institutions Murdoch University (WA): The Key Centre director has an adjunct appointment at Murdoch University to help co-ordinate the implementation of a new undergraduate degree in Renewable Energy Engineering. The closest liaisons are with those most closely involved in developing the program, Dr. Martina Callais and Professor Phillip Jennings. Professor Jennings is also a member of the Key Centre Advisory Committee. Professor S.R. Wenham is also a member of the Murdoch University Renewable Energy Engineering Board. Staff members from the Key Centre visit Murdoch University several times each year to assist with program development and implementation. The Key Centre has made available several of its courses for students enrolling in this new degree at Murdoch University which commences in 2001. A joint paper has been published relating to the programs being developed under this collaboration. (Wenham, S. R., Outhred, H., Jennings, P., Lee, P., New Undergraduate Engineering Programs in Renewable Energy, 7th International Symposium on Renewable Energy Education, Oslo, June 2000.). Massey University, (NZ): Ralph Simms is an international expert in biomass, an area needing to be covered in the new engineering degree. With funding from the Australian CRC for Renewable Energy, Ralph Simms is developing a course on biomass to suit the new Key Centre undergraduate degree and also the Murdoch University Renewable Energy Engineering degree. The Australian National University (ACT): Dr. Keith Lovegrove has particular expertise in solar thermal systems. The Australian CRC for Renewable Energy is again providing funding to enable Keith Lovegrove to develop material for a new course in the solar thermal area that will be made available to the educational programs at Murdoch University, UNSW and the ANU. Associate

Professor Andres Cuevas from the ANU is also a member of the Key Centre Advisory Committee. University of South Australia (SA): Associate Professor Wasim Saman is the Director of the Sustainable Energy Centre at the University of South Australia and the designated Chair of the ISES 2001 Solar World Congress, Scientific/Technical Program Committee. Professor Saman has invited Professor S. Wenham (Director of the Key Centre) to serve on this organising committee, with the invitation gratefully accepted. Georgia Institute of Technology (USA): A collaboration has been established with the Key Centre in the area of developing new teaching programs. To assist, one of the Key Centre staff members, Associate Professor C.B. Honsberg, has made a couple of visits to the Georgia Institute of Technology. The second of these visits is in early 2001 and will be for a lengthier period to facilitate the establishment of new core teaching in the area of photovoltaics and solar energy for the first and second year programs at the Georgia Institute of Technology. Professor Honsberg is also assisting with the implementation of a new research program to be based on the UNSW BCSC technology. Through this collaboration, easier access is provided for the Key Centre to the US industry and manufacturers. An example of this has already occurred with one of the US manufacturers establishing an industry collaborative research project with the Georgia Institute of Technology to work on this UNSW BCSC technology. The main contact in the educational area is Professor Ajeet Rohatgi while the contact in the research area is Dr. Ebong Abesfreke. Loughborough University (UK): The liaison and collaboration established with the Key Centre focuses on the development of teaching resources and materials and the sharing or exchange of such materials. Dr. Paul Rowley from the Centre for Renewable Energy Systems Technology (CREST) at Loughborough University initiated this collaboration to gain access to Key Centre teaching materials. De Montfort University (UK): The Key Centre has established a link with the Institute of Energy and Sustainable Development at De Montfort University. Sara Batley-White initiated this collaboration with the Key

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Centre with exchanges and sales of materials having already taken place. For example, the Key Centre has made available the material on the CDROM “Photovoltaics” produced by Associate Professor C.B. Honsberg, as a teaching tool at De Montfort University. In addition, they have purchased the rights to include the same material on a CDROM produced at the Institute of Energy and Sustainable Development, for distribution to the students. Delaware University (USA): A long-term close link has existed between UNSW and Delaware University with several staff exchanges having taken place over several years. Professor Allen Barnett, who is also the President of the major US manufacturer, AstroPower, is a member of the Key Centre Advisory Committee. Oregon Insitute of Technology (USA): A former PhD student from within the Key Centre has taken on an academic position at the Oregon Institute of Technology. Apparently, the appointment was made with the intention of establishing a closer liaison with the Key Centre to help with the establishment of new educational programs in the photovoltaics area at the Oregon Institute of Technology. Bradley O’Mara is likely to make regular visits between the two institutions and is likely to carry out some teaching in both. A new course on the use of electronic interfaces in photovoltaic systems has been proposed for development by Bradley O’Mara for use at both institutions. Northern Territory University (NT): A close liaison has existed for many years between the Key Centre and NTU by virtue of the solar car project at NTU. The Key Centre has provided the solar cells for the NTU vehicle with a former photovoltaics student from UNSW (Byron Kennedy) also joining the staff at NTU. University of South Carolina (USA): The main contact person at the University of South Carolina is Professor Dean Patterson who is currently on sabbatical from Northern Territory University. During his sabbatical, Prof. Patterson is establishing some new educational programs in collaboration with the Key Centre, for implementation at the University of South Carolina. The Key Centre has given permission for Professor Patterson to use various Key Centre teaching materials such as in the delivery of a new course on “Applied Photovoltaics” to be

offered at the University of South Carolina in 2001. Darmstadt University of Technology (Germany): This is a somewhat different but interesting linkage as Darmstadt University is primarily interested in education in the architectural area. Silke Krawietz has indicated a wish to establish an on-going linkage that will provide Darmstadt University with access to educational materials that can be used and applied to the architectural area. As a follow up, Silke Krawietz visited the Key Centre during September, 2000 to formalize the collaboration. TAFE Colleges: The Key Centre has various links with TAFE colleges both on the East coast and West coast of Australia, primarily for the purpose of keeping abreast of the educational programs being offered by each institution. For example, Trevor Birrell from Ithaca TAFE in Queensland, is coordinating a new syllabus for renewable energy TAFE courses nationwide. However, the potential for collaborative and combined programs is also being explored through the Key Centre's collaboration with Murdoch University (MU). The option has been made available for students to complete 3 MU units (worth 9 points) plus 2 years of study in a suitable diploma program at TAFE, to then qualify for exemption from two years (48 points) of the Bachelors program at MU. This collaboration is through the Challenger TAFE, but likely to be expanded to include e-Central TAFE in Northbridge which offers the Certificate IV Renewable Energy Technology. So far only two students have taken this option, both enroling in the Bachelor of Technology program. Thailand Universities: The Centre for Photovoltaic Engineering has also establish an ongoing collaboration with several institutions in Thailand. The Centre hosted three Thai university academics for eight weeks as part of the Thailand-Australia Science and Engineering Assistance Project (TASEAP) sponsored by the Kingdom of Thailand Ministry of University Affairs and the Australian Agency for International Development. The TASEAP Fellows came from Chaing Mai University and Burupa University, both of which have strong teaching and research interests in photovoltaics and renewable energy.

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The Centre also has well established links with a large number of research institutions that are less involved with industry collaborative research projects and corresponding teaching programs. These are listed in the annual report for the Photovoltaic Special Research Centre whose research activities are more closely aligned to those at each respective institution. • Linkages with other industry

organisations and end users Pacific Power: For several years, Pacific Power has provided excellent support for Key Centre activities both in terms of assisting with educational programs and also in supporting research activities. Pacific Power is a major player in the electricity industry and is becoming a major user of renewable energy technology. Robert Marlon has provided the Key Centre with educational material in the area of wind generation and has also assisted with lecturing. Pacific Power is also the major shareholder in Pacific Solar, a company established to commercialize UNSW solar cell technology. Robert Marlon is a member of the Key Centre Advisory Committee with particular expertise in the area of wind generation of electricity. Integral Energy (NSW): As an energy provider, Integral Energy has for several years been increasing its activity with grid-connected photovoltaic rooftop systems. An initial collaboration was established between Integral Energy and the Key Centre when problems were occurring witin some of these systems commissioned several years ago. Integral Energy have expressed its willingness to have students from the new degree involved in photovoltaic related projects conducted and supervised by Integral Energy staff, although as yet no such arrangements have been formalised. The contact with Integral Energy was established many years ago through Geoff Stapleton, who has subsequently become a member of the Key Centre Advisory Committee. EnergyAustralia (NSW): Energy Australia has been a financial contributor to the energy efficient photovoltaic powered facilities owned by UNSW at Little Bay. The manager of the Sustainable Energy Branch at EnergyAustralia is Neil Gordon. Ergon Energy (Queensland): Ergon Energy is an energy provider in Queensland with a range of renewable energy interests and

activities. Michelle Guelden, the company’s Project Engineer, has established close links with the Key Centre and participates in regular meetings with Key Centre staff. The next meeting is scheduled for March 2001. Western Power Corporation (WA): Western Power owns all the electricity grids in WA and established close links with the Key Centre several years ago when it needed additional expertise in the renewable energy technology area. Lack of appropriately trained engineers has led Western Power to be a large financial contributor to the development of new engineering programs in the renewable energy area. During 1999, Western Power awarded Professor S.R. Wenham from the Key Centre the Western Power Chair in Renewable Energy Engineering to co-ordinate the establishment and implementation of the new undergraduate degree in Renewable Energy Engineering at Murdoch University. Due to commitments to the Key Centre, Professor Wenham was only able to take on these tasks as an adjunct appointment at Murdoch University. Western Power has provided the bulk of the funding required for the establishment of this new degree. Solar Electric Power Association (International body of electric utilities): The Solar Electric Power Association (SEPA) grew out of the former UPVG, an association of US utilities. This is now an international association of electric utilities with Peter Lawley as a director on the board. Peter Lawley is a member of the Key Centre Advisory Committee. The Sustainable Energy Industries Association of Australia (SEIA): Geoff Stapleton has been the NSW president of SEIAA for many years. He is also a member of the Key Centre Advisory Committee. The Olympic Business Roundtable Committee (NSW): Mr David Hogg, a member of the Key Centre’s Advisory Committee, has been a member of the State Government’s Olympic Business Roundtable Committee during 2000 and previous years. This committee has been responsible for the Australian Technology Showcase. Australian New Zealand Solar Energy Society (ANZSES): Dr. A. Sproul, a member of the Key Centre academic staff, is a former secretary of the national body of ANZSES. He, along with David Hogg and Peter Lawley,

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are also individual members of ANZSES, with the latter two also being members of the Key Centre Advisory Committee. National Parks and Wildlife Service (NPWS): NPWS has been collaborating closely with the Key Centre as it has been scaling up its use of photovoltaics. For example, the Key Centre has two on-going joint projects with NPWS, Montague Island National Park (off of Narooma, NSW) and Green Cape National Park (Eden, NSW). Both of these sites have installed Key Centre designed/specified hybrid renewable energy systems amalgamating 4 kWp PV arrays and battery storage with existing diesel generation. NPWS has contributed to several Key Centre publications and are supporting undergraduate education (both 4th year thesis, and 2nd year project work) through on site student project work involving data acquisition and data analysis. CSIRO: Jim Edwards is the group manager for the Renewable Energy and Energy Storage Technologies. Several meetings have been held between the Key Centre and the group led by Jim Edwards to facilitate collaboration in the renewable energy area. CSIRO is currently investing heavily in the establishment of new renewable energy activities in the Newcastle area and have indicated their intention to collaborate with the Key Centre to avoid duplication of infrastructure and activities particularly in the photovoltaics area. Once fully established, Jim Edwards has indicated the willingness of his group to have students from the new Key Centre degree involved in project work in association with his group, particularly in the new CSIRO facilities in Newcastle. Electricity Supply Association of Australia (ESAA): The ESAA has a range of activities of relevance to the Key Centre. Several linkages therefore exist. Ted Spooner chairs the standards sub-committee established to convert the ESAA guidelines into Australian standards in the photovoltaics area. Ted Spooner is an academic staff member within electrical engineering at UNSW and is an adjunct member of the Key Centre for Photovoltaic Engineering. Peter Lawley, a member of the Key Centre Advisory Committee, is also a member of this standards sub-committee. Peter Lawley is also a regular speaker at the ESAA Renewable Energy Conference held every 18 months.

The Sustainable Energy Development Authority (SEDA): The executive director, Mark Fogarty, of SEDA in NSW is a member of the Key Centre Advisory Committee. SEDA also provides funding for the on-going development of the new engineering degree in Photovoltaics and Solar Energy. Various negotiations have also taken place between SEDA and the Key Centre for the establishment of student projects under the supervision of SEDA staff. Renewable Energy Action Working Group: Peter Lawley is a member of the Working Group established by the Department of Industry, Science and Resources. This Working Group was responsible for the formulation and implementation of the Renewable Energy Action Agenda of June, 2000. Peter Lawley is also a member of the Key Centre Advisory Committee. Murdoch University Energy Research Institute (MUERI): Close links exist between the Centre and MUERI, particularly through the MUERI director, Trevor Prior. This collaboration is in the educational area with students from the new engineering degree in Photovoltaics and Solar Energy at UNSW already benefiting through enrolment in on-line courses offered by Trevor Prior in the area of remote area power supplies. The Australian CRC for Renewable Energy (ACRE): ACRE has been a strong financial supporter of the Key Centre activities both in terms of funding course development but also in relation to various activities within the Key Centre such as running short courses, offering internet based courses and running events such as the model solar car race SUNSPRINT for high schools. Professor Phillip Jennings is responsible for the area of education within ACRE and he is a member of the Key Centre Advisory Committee. The Chairman of the ACRE board, Dr. Bruce Godfrey, is also a member of the Key Centre Advisory Committee. ACRE has also provided the Key Centre with excellent support through providing access to educational material that has been developed by ACRE staff over several years. Office of the Board of Studies NSW: The Key Centre has established excellent links with the Board of Studies in NSW which is responsible for high school education in NSW. Teresa Renneberg of the Board of Studies has invited the Key Centre to participate in the annual lecture series

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provided to the students from approximately 100 high schools around the State. Approximately 1600 Year 12 high school students attend these lectures at the Power House Museum in February each year, with the Key Centre staff giving 32 lectures on the topic of innovation. This is an excellent environment through which to disseminate information on the latest research achievements and results to a large number of high school students and teachers and indirectly to their corresponding families. The Key Centre staff have also been asked to prepare appropriate corresponding documentation to aid the students in their studies for the higher school certificate. This written material is reviewed by the Board of Studies prior to distribution to all the high school students attending the lectures. Institute of Engineers Australia (IEAust): The Key Centre Director is a Fellow of the Institute of Engineers Australia which keeps the Key Centre abreast of IEAust activities. Two of the Key Centre academics, Professor S.R. Wenham and Dr. J. Cotter, are members of the Faculty IEAust Accreditation Committee. This committee will work closely with the Institute of Engineers Australia during 2001 in preparation for gaining accreditation for the various engineering degrees at UNSW. David Hogg, a member of the Key Centre Advisory Committee is also a member of the IEAust National Committee on Fuels and Energy. The Energy Policy Group (AEPG): The Key Centre is involved with ACRE's Energy Policy Group (AEPG). Muriel Watt is Group leader and Hugh Outhred a Group member. Other members are drawn from academia, industry organisations, the private sector and government. The aim of the AEPG is to contribute authoritatively to selected issues involving renewable energy. It delivers analyses on the impact of proposed policies on the uptake of renewable energy and the development of the indigenous Australian renewable energy industry. The Group also seeks to provide comparison of various policy options in this regard and to advise ACRE on policy issues and its own strategic planning. During 2000, AEPG was approached by government agencies and by Senate Committees for comment on a renewable energy programs, greenhouse gas strategies and energy policy issues. Members appeared before Senate Committee hearings on Australia’s greenhouse gas reduction strategies and the renewable energy target

legislation. Work is underway on an energy efficiency policy report. Aid Organisations The importance of Aid Organisations in facilitating the use of photovoltaic and other renewable energy technologies in developing countries has led to the Key Centre establishing several links with organisations such as The Himalayan Light Foundation (Andrew Warboys, Co-ordinator of Sola Sisters Program), AusAid (Bruce Robins, BP Solar employee responsible for projects with AusAid) and the Uniting Church of Australia (Rev Laurie Fitzgerald, responsible for various overseas aid projects including some with AusAid support). Himalayan Light Foundation (HLF): The most well developed links with an aid organisation are those with the HLF, who is co-ordinating the involvement of students from the Key Centre to participate in a project for the design, implementation and testing of photovoltaic systems in remote villages in Nepal. Two Key Centre staff members visited the HLF in October 2000 to formulate the project details and arrangements. The first group of six Key Centre students are scheduled to travel to Nepal to participate in this project in late September 2001. The establishment of this collaboration has been aided by the involvement of Andrew Warboys, the Program Co-ordinator for the Sola Sister’s Program at the HLF, who is a previous photovoltaics student of the Key Centre staff. • Networks and collaboration with other

organisations involved in education The success in this area can be ascertained from the above list although the Key Centre retains the ongoing aim to keep establishing new linkages with organisations important to the industry and therefore to the Key Centre activities. In particular, in the area of photovoltaic and renewable energy education, extensive collaboration and networking has been established with a range of institutions and organizations involved. These are also described under "Teaching" and also in the accompanying general Key Centre report. The Key Centre has been particularly effective at establishing collaborations that will aid either the teaching activities within the Key Centre or else where the Key Centre is able to aid the teaching activities elsewhere.

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• National and International Promotion In the area of promoting the Key Centre activities nationally and internationally, the extensive linkage network described above facilitates such promotion quite effectively. In addition, the Key Centre regularly publishes material at the major international conferences covering the teaching and research activities of the Key Centre. Considerably more detail is reported in the accompanying general Key Centre report describing the extent and effectiveness of the different forms of promotion of the Key Centre activities. • Collaborative research projects with all

Australian PV manufacturers As reported in last year’s Annual Report, the Key Centre successfully established collaborative research projects with all existing Australian photovoltaic manufacturers, even though the target for achieving this was not until 2004. These collaborations have been somewhat simplified by the merger between the two Australian manufacturers, BP Solar and Solarex, and also the large scale investment of the Italian company, Eurosolare, in the Australian company Pacific Solar. Further details on this performance indicator are provided under the above heading of "Research" and also in the accompanying general Key Centre report.

• IEAust Accreditation The issue of IEAust accreditation for the undergraduate degree in Photovoltaics and Solar Energy was raised and discussed under the section of “Teaching”. As was explained, IEAust regulations prevent the achievement of accreditation until students have completed the program and had at least one year of experience in the industry. Nevertheless, two of the Key Centre academic staff members are liasing with the Institute of Engineers Australia on the topic of accreditation as they serve on the Faculty committee for IEAust accreditation in engineering. • Fortnightly seminar series The fortnightly seminar program was successfully established during 1999 as reported in last year’s Annual Report. This fortnightly seminar program is run jointly between the Key Centre for Photovoltaic Engineering and the School of Electrical Engineering under the direction of Associate Professor Hugh Outhred and Mr. Ted Spooner. This seminar series has successfully continued throughout the year 2000. Topics such as global warming, the restructuring of the electricity industry and the potential role for renewable energy technologies have been particularly well attended.

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4. KEY CENTRE INCOME Introduction As shall be seen from the financial statement for the Key Centre, there is considerable leveraging of the ARC funds which make up less than 1/3rd of the total Key Centre income. This is particularly important in terms of the Key Centre establishing sustainability in the longer term. During the remaining four years of operation of the Key Centre, it will be necessary to continue to develop the other income sources to fully replace the ARC funding through the Key Centre scheme. The prospects for doing this look particularly good with EFTSU income poised to increase each year as more students enter the undergraduate BE and postgraduate MEngSci programs. The operating expenses are also currently high and will remain high for the next few years due to the on-going development of new teaching materials and courses for these new educational programs. The on-going development of the teaching laboratory in terms of developing new experimental apparatus and demonstration systems will also remain a high expense for several years. In the longer term, many of these costs will fall while the EFTSU income will rise, such that by 2005 when the Key Centre funding ceases, financial independence and sustainability should be achieved. The pie chart below shows the relative proportions of the various Key Centre income sources. The following gives additional details in relation to the financial statement and the different sources of income.

ARC Centre Grant

Other ARC Grants

Industry/Private Funds

Contracts/Consultancies

Host Institution Support

Other IncomeSources/Interest

Other ARC Grants Two of the industry collaborative research projects have been considered worthy for funding under the ARC SPIRT scheme. The

industry collaborative research projects are managed by staff of the Key Centre, although Key Centre funds from the ARC are not used to support the costs of the actual research projects as these are all self-funding. The Key Centre has had considerable success in establishing such collaborative research projects that are funded by industry. Additional details are provided in the section under "Research" and also in the accompanying general Key Centre report. During the year 2000, $291k income was received from the ARC through the SPIRT scheme. These projects, however, are nearing completion and so this income source is expected to reduce in future years. Other Commonwealth Government Funds There are no other Commonwealth Government funds received by the Key Centre except for those originating from DEETYA in the form of “equivalent full-time student units” (EFTSUs). In accordance with the ARC reporting guidelines for Key Centres, income from this source has been listed under “host institution support”. Industry/Private Funds The income sources in this category are provided to support both research and teaching activities within the Key Centre. The major contributors for the educational programs are the Australian CRC for Renewable Energy and to a lesser extent the Sustainable Energy Development Authority of NSW. Industry contributions, although quite large and important, tend to be in-kind rather than cash contributions. In the area of research support, the bulk of the funds are contributed by Pacific Solar, BP Solar and Eurosolare, through the various collaborative research projects during the year 2000 as listed in the section under “Research”. These funding sources, particularly in the research area, have proved themselves to be self-sustaining with no Key Centre ARC funding required to support these activities. With the massive expansion taking place in the industry and the growing importance of UNSW technology in the market place, these types of collaborative research projects and the corresponding income sources they generate are expected to continue to increase year by year.

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Contracts/Consultancies Centre staff engage in a range of consultancies and contract based projects in both the research and educational areas. There is often only a fine distinction between this type of work and some of the collaborative research and teaching activities with other institutions, companies and organizations. In general, the contractual or consultancy work is relatively short term and in general involves the provision of expertise or training. This type of income may vary significantly from one year to another and in general involves a range of different sources and also involves a range of our academic staff. The Key Centre policy is to allow those that earn such consultancy income to then make decisions on how it is spent provided earning the income has not involved the Centre in other expenses. Key Centre staff are also involved in a large number of consultancies with companies that have licensed UNSW technology. Often, the income from this work does not appear as a direct income under this category as the rewards for such work are often forthcoming in the form of royalties at a later date through manufacturing of the technology. Income through licensing fees, technology transfers and general consultancies of this type go directly to Unisearch, the commercial arm of the University. This income is used to cover a range of expenses associated with the exploitation of the technology such as marketing, patenting expenses, the laboratory costs for technology transfers, etc.. Once all the costs are covered, a portion of the proceeds becomes income to the Key Centre which is then distributed to the group or researchers responsible for the particular technology. Such income therefore does not appear under this category but instead will for instance appear within the financial statement of the Photovoltaic Special Research Centre (PVSRC) which although no longer funded by the ARC is able to operate through the use of income generated through previous commercially orientated activities of the PVSRC. Host Institution Support The host institution support for the Key Centre has been excellent, exceeding that foreshadowed in the original Key Centre proposal. The $890k listed in the financial statement has several components. The first component of $100k per year comes directly

from the Deputy Vice-Chancellor. The second component of $135k provides for the Key Centre director’s salary plus oncosts to ensure that the Key Centre director is relieved from teaching or administrative duties that would otherwise distract from his management and direction of the Key Centre. The third component comes from the Faculty of Engineering and is again an annual commitment, this time for $150k per annum. This component was not foreshadowed in the original Key Centre proposal but is awarded on the basis that the Key Centre is now operated as an independent budget unit within the UNSW system with its own educational programs. This component aims at providing additional administrative support particularly for the teaching activities of the Key Centre. This support will continue indefinitely, beyond the date at which the ARC financial support for the Key Centre ceases. The host institution support includes three other sources of income that the Key Centre is able to earn through its activities by virtue of the fact that UNSW now treats the Key Centre equivalently to an independent budget unit. One of these is based on the research quantum, which is earned as a function of funding attracted from industry sources and national competitive grants. Because of the very strong research performance of the Centre in the photovoltaic area, the research quantum component is quite large amounting to hundreds of thousands of dollars each year. These funds are distributed to the activities responsible for earning the income with a large share therefore being distributed to the Special Research Centres in the photovoltaic area. The remaining component of $81k was generated primarily by the Key Centre activities and therefore appears as income under this heading. The other two major components of income in this category are calculated based on EFTSU values for the Centre for Photovoltaic Engineering. For the year 2000 these two components combined amounted to $424k, approximately $180k relating to PhD and ME enrolments, with the remainder based on EFTSU’s derived from undergraduate enrolments. The former is an area where the Key Centre is performing strongly and an area of income that will grow year by year as the total number of postgraduate research student enrolments continue to increase. The latter component will grow even more significantly in the future as more students enrol in the new undergraduate engineering program in

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Photovoltaics and Solar Energy. Last year, being the first year for the new degree, the teaching income was relatively small, exacerbated by the fact that our students only enrol in two photovoltaics related courses during their first year. In several years, this component is expected to grow to well in excess of $500,000 each year at which stage the Key Centre will be self-sustaining in terms of being no longer reliant on ARC funding. In addition to the direct financial support described above, the host institution provides additional large levels of indirect support such as through the provision of accommodation, services, infrastructure support, scholarships, post-doctoral fellowships, laboratory consumables etc Other Income Sources The most significant component in this category results from the sale or licensing of educational materials developed by the Key Centre. It includes the books and multimedia CDROMs that have been produced and in some instances published specifically as textbook material for students taking the courses in the new Key Centre educational programs. The sale of such educational materials appears to be increasing significantly each year, firstly because of the growth in the industry and secondly because of the increased range of resources available from the Key Centre for sale or licensing to students and other institutions. Three new CDROM’s are currently under development for use in three of the Key Centre courses. One of these relates to the course on “Photovoltaic Technology and Manufacturing” and contains a virtual

production line which has been developed in conjunction with industry. Students will be able to operate this virtual production line by taking control of all pieces of equipment and the corresponding processing parameters. The CDROM contains all the necessary analysis and modelling software to facilitate measurement of all the important device parameters at the end of the simulated production. This is a particularly powerful educational tool which has attacted the interest of many commercial companies as well as the engineering students. The second CDROM currently under development is one based on photovoltaic systems. This is a partner CDROM to the one previously produced by Associate Professor C.B. Honsberg on “Photovoltaics: devices, systems and applications”. This latter CDROM has already sold approaching 1,000 copies despite only being released approximately one year ago. The third CDROM currently under development is one based on the second edition of the book, “Speed of Light” by Dr. J. Cotter. This CDROM focuses on the design and development of solar cars covering in detail all the state-of-the-art technologies and their use. The CDROM includes simulated race conditions and presents design strategies for students to learn and exploit as they engage in their own exercises of designing and developing solar cars. All three of these CDROM’s are expected to be successful commercially and will therefore lead to additional income in this category. All three are targeted for completion in late 2001 or early 2002.

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5. COMMERCIALIZATION AND TECHNOLOGY TRANSFER

The Key Centre has a particularly strong record in terms of technology development and transfer to industry. The Centre has licensees in many of the major countries including the USA, Australia, Germany, Spain, Italy, South Korea, India and the UK. In fact, the buried contact solar cell technology has become the most successfully commercialized new photovoltaic technology internationally in the last fifteen years in terms of product deployed in the field. In the Annual Report last year, details were provided of a new license entered into with the Italian company, Eurosolare. The corresponding technology transfer has taken place during 1999 and 2000, with further technology transfer planned for the end of February, 2001. The technology licensed by Eurosolare is the latest generation of BCSC, with the on-going collaborative developments therefore necessitating on-going technology transfer. Each of the collaborative research projects with industry have their own components of technology transfer. This is an essential ingredient built into each of the collaborations. For example, Linda Koschier from the Key Centre travelled to BP in the UK to carry out the technology transfer associated with the research project 1.1 listed under the “Research” heading. Another example was when two PhD students travelled to Eurosolare in Rome during the year 2000 to aid in the technology transfer of

the latest developments from UNSW. The research projects with Pacific Solar focus more on the commercialization of technology rather than on technology transfer. Pacific Solar has previously purchased or licensed the relevant technologies from UNSW with the collaborative research projects focussing on UNSW staff providing access to expertise, testing and characterization facilities to aid Pacific Solar’s commercialization efforts. A good indicator to the success of this work has been the successful establishment of a pilot production facility at Pacific Solar six months ahead of schedule for producing thin film polycrystalline silicon photovoltaic modules. In the other collaborative research project with Pacific Solar, the provision of expertise and access to facilities has accelerated Pacific Solar’s development and commercialization of their new inverters for interfacing photovoltaic panels to the electricity grid. These inverters have been successfully commercialized and made available on the market since mid-2000. Greater details on these activities are provided in the “Research” section and also in the accompanying general Key Centre report. Commercialization of technology and the requirement for technology transfers are expected to be on-going in an industry that is rapidly expanding. Two new companies are currently negotiating licensing agreements with the Key Centre – one for the manufacture of an adapted high efficiency version of the BCSC and the other for concentrator cell technology.

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6. AGREED PERFORMANCE INDICATORS The agreed performance measures and expected outcomes were listed in the original Key Centre proposal. Progress against most of these agreed performance indicators has been discussed under the relevant headings in this report. The only significant statistical data relates to student numbers enrolling in the new undergraduate engineering degree in Photovoltaics and Solar Energy. As already indicated, the Key Centre has been highly successful at attracting the target number and quality of students into this program, with 41 students commencing the program in the year 2000, well above the target range of 25-35 students. Progress against all of the other performance indicators is treated elsewhere in this report under the relevant headings except for progress towards sustainability. Sustainability An important step towards facilitating the Key Centre’s achievement of sustainability was its establishment as an independent budget unit within the UNSW financial system. This provides the Key Centre with the opportunity to generate new income sources, particularly through EFTSUs and Research Quantum income generated through the Key Centre’s teaching and research activities respectively. In Section 4 of this report relating to Key Centre income it is clear that excellent progress is being made towards demonstrating the Key Centre’s ability to become self-funding and self-sustaining in the longer term. Of particular importance has been the implementation of the new undergraduate engineering degree in Photovoltaics and Solar Energy which has already demonstrated that it can attract the required numbers of enrolments to provide the Key Centre with adequate income sources in the long term to be self-sustaining. The agreed performance measures and expected outcomes from the original Key Centre proposal are as follows: • Establish the KCTR as an independent

budget unit within the UNSW financial system with appropriate share of income from UNSW operating grants.

This task has been successfully completed on schedule with the relevant new income sources listed in Section 4 under the heading of Key Centre Income.

• Establish new, reliable income flow by

the end of 2004. Excellent progress has been made towards the ultimate goal of achieving sustainability without relying on ARC Key Centre income. The first year of operation without ARC funding will be 2005 at which time the expected income and expenditure will be as follows: ($'000s) Expenditure (steady-state) Academic Salaries (7) 630 Administrative Support (2) 90 Office Manager 60 Business & Technology Manager 50 Financial Officer (0.5) 30 Technical Support (2) 110 Education Officer 60 General operating expenses (10% of the above) 103 Teaching development, Equipment & infrastucture support 274 TOTALS 1407 ($'000s) Income (steady state) Undergrad teaching (1.8 EFTSU/ student (4-year course) with 40-60 students/year) 567 Postgrad Teaching (15 EFTSU) 105 PhD students (25) 325 Research Quantum 200 Other courses (general ed + internet) 30 Book and teaching material sales 30 Dean's contribution 150 TOTALS 1407 • Appoint KCTR personnel from the

management structure to tenured positions to provide security and stability.

The academic positions for Dr Jeff Cotter and A/Professor Armin Aberle have now been converted to tenured appointments. The latest academic appointment for Dr Alistair Sproul does not at present have provision for tenure, but with the expectation that the position will be converted to one with provision for tenure within twelve months. The other Key staff from the management structure are: Mark Silver (Business & Technology Manager); Robert Largent (Education Officer); Lisa Cahill/Jenny Noble (Office Manager); Julie Kwan (Financial Officer); and Jenny Hansen

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(Administrative Support). All now have positions funded by the Key Centre that are equivalent to tenured positions. • Tailor activities of the KCTR to ensure

expenditure balances steady state income by the end of the six year funding by the ARC.

The Key Centre has been focussing on the development of activities and income sources that are believed to have the potential to be self-sustaining and self-funding. All of the collaborative research projects with industry have already demonstrated their ability to be self-funding. Of the other Key Centre activities documented in this report, most are either already self-funding or have at least demonstrated a high probability that they will become self-funding in the future. The promotional and marketing activities of the Key Centre do not directly generate income but are an essential investment of Key Centre resources to facilitate the establishment and sustainability of other Key Centre activities. Progress towards ensuring that expenditure

will balance the steady state income by the end of the six year funding period from the ARC can be best judged from the above table showing the expected income and expenditure for the Key Centre for the year 2005. There appears to be a high probability that sustainability will be achieved on schedule by the end of 2004. • Demonstrate ability to attract students

to the new undergraduate degree program.

This has been successfully demonstrated with the enrolments for the year 2000 and 2001 both exceeding the target levels. • Generate new income sources such as

teaching, licensing technology, royalties, consulting and new collaborative research agreements.

The Key Centre has made excellent progress in each of these areas of income generation. Greater details are provided in Section 4 under the heading of Key Centre Income.

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7. KEY CENTRE EXPENDITURE The pie chart below gives the breakdown in expenditure of ARC Key Centre Funds during the year 2000.

SalariesEquipmentAccommodationTravelConsumables

Salaries The total spent on salaries for the year 2000 including on-costs was $132,355. The five largest components of this expenditure are as follows: The largest salary component was for the Educational Officer of the Key Centre, Robert Largent, a full time appointment. Rob Largent’s responsibilities also included coordinating the promotional activities for the Key Centre, particularly with regard to producing and disseminating information about the new educational programs. This salary component amounted to $51K. The second largest salary component was that of Jenny Noble, who initially provided secretarial support for academic staff within the Key Centre, but was promoted to full-time Office Manager for the last few months of the year 2000 as a replacement for Lisa Cahill who was absent on maternity leave. The Office Manager is a full-time appointment with the primary responsibilities being to manage the Centre office that runs and coordinates the teaching activities and teaching programs. The corresponding salary component was $31k. The third largest salary component was that of Dr. Muriel Watt, a part-time academic staff member who has been employed to develop several courses in the new undergraduate engineering degree in Photovoltaics and Solar Energy. This salary component was approximately $18k. The fourth largest component of $12k was for the part-time employment of a computer programmer who focuses primarily on the multimedia development of educational materials. The staff member employed for

this purpose was Anna Bruce. The fifth largest component of the salaries was $7k, paid to a graphic artist, Melissa Machulski, who has been employed on a casual basis to assist with the presentation of teaching material and reports such as the Key Centre annual report for 2000. Equipment During the year 2000, the ARC Key Centre funds spent on equipment amounted to $56,637. The largest component was a new fileserver which cost approximately $11,000 and has been purchased to enable the dissemination of information over the internet. This includes the ability to offer on-line courses such as “Applied Photovoltaics” which was delivered over the internet in March/April, 2000. A range of other types of information is also made available on the Centre’s website for access externally via the internet. The second largest equipment expense was for a multimedia projector valued at approximately $9,000 for use in lectures and seminars. No other pieces of equipment cost over $5,000. Most of the remaining expenditure was for relatively small items of equipment that are for use in experimental apparatus for the purpose of student projects such as data loggers and pumps or else in the purchase of basic computers for use in the Key Centre computer laboratory by the new undergraduate students enrolling in the Engineering degree in Photovoltaics and Solar Energy. Some small items of equipment have also been purchased for use in the Centre office for administration purposes. Accommodation The only ARC Key Centre funding spent on accommodation was for the purposes of hiring hotel rooms or equivalent for Key Centre academic staff members when away on trips relating to Key Centre activities. The total expenditure in this category was only $4,295 for the year 2000. Travel The total ARC Key Centre funds spent on travel during the year 2000 was $8,807. This was used as partial funding for four trips, three domestic and one international. One of these trips was to facilitate a trip by

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Anna Bruce to Europe to visit a company, Eurosolare, in Rome who had given permission to the Key Centre to video their manufacturing facilities for the purpose of producing multimedia educational material for the new engineering degree in Photovoltaics and Solar Energy. The three domestic trips partially supported with ARC Key Centre funding included a visit by the Key Centre director to Murdoch University to assist with the development and implementation of a new undergraduate degree in Renewable Energy Engineering. The second domestic trip involved partial funding for Dr. Jeff Cotter to travel to the Northern Territory to gather information from the World Solar Challenge relevant to the new CDROM being produced for one of the courses in the new degree program. The third domestic trip was for the travel of Professor Phillip Jennings from Murdoch University to attend UNSW to provide assistance with educational programs and to participate in the Key Centre Advisory Committee meeting. Materials and Consumables During the year 2000, $165,110 was spent on consumables relating to Key Centre activities. Many of these consumables related to expenses associated with the development of new teaching materials and resources. The other major component of consumable costs related to funding teaching activities and the operation of the Centre office that was

established specifically to provide the administration and coordination of the educational programs. These included costs such as printing, photocopying, telephone usage, stationary, etc. None of ARC Key Centre funding was used to support the research activities of the Key Centre which have already demonstrated themselves to be self-sustaining and self-funding. Other Expenditure There was no other expenditure of ARC Key Centre Funds other than that which has been categorised under the above headings.. Carry-Forward The carry over amount of $126,799 is requested for use by the Key Centre in the year 2001. This amount is significantly less than the $183,000 that was carried forward into the year 2000. This indicates that the Key Centre has managed to catch up on some of the expenditure originally earmarked for the year 1999. This has been possible due to the availability of the space allocated to the Key Centre for the purpose of developing a new teaching laboratory in photovoltaics. The development of this teaching laboratory will continue during 2001, therefore necessitating the carry over of unspent funding into the year 2001.

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9. KEY CENTRE MANAGEMENT Overview An overview of the Key Centre management and its governing committees is provided on the next page. The accompanying general Key Centre report also includes a brief overview of the Management Committee and the Advisory Committee for the Key Centre on pages K8 and K9. Advisory Committee The Advisory Committee met once as planned during the year 2000, with the preferred mode of communication often being via email due to the diverse geographical locations of many of the Advisory Committee members. The majority of the Advisory Committee membership and their corresponding affiliations are listed on page K9 of the general report attached. In recent months, however, there have been four new members appointed to the Advisory Committee whose details are as follows. Dr. Francesca Ferrazza Dr. Francesca Ferrazza is the Director of Research of the Italian company Eurosolare. Eurosolare has a major industrial collaborative research project with the Key Centre and has recently become a significant shareholder in the Australian company, Pacific Solar Pty. Ltd.. Dr. Ferrazza is recognized as one of the leading European researchers while Eurosolare is one of the largest European manufacturers. Eurosolare is also a licensee of the new generation of buried contact solar cell technology licensed from the Key Centre. Peter Lawley Peter Lawley is well connected within the industry, particularly with many of the organizing bodies and groups. He is a director on the Board for the Solar Electric Power Association (formerly the UPVG of USA utilities). SEPA now has membership of utilities internationally. Peter Lawley is also a member of the standards sub-committee and a

regular speaker at the ESAA Renewable Energy conferences. He is also the Business Development Manager and Company Secretary for Pacific Solar Pty. Ltd. and a member of the Renewable Energy Action Working Group established by the Department of Industry, Science and Resources. Dr. Zhengrong Shi The third new member of the Advisory Committee is Dr. Zhengrong Shi, a senior manager for the company Suntech Power Company Ltd. in Wuxi, Peoples Republic of China. Dr. Shi is recognized as a world leader in thin film polycrystalline silicon photovoltaics and is particularly well connected throughout Asia. Mark Fogarty The other change in membership of the Advisory Committee has been the inclusion of Mark Fogarty, the Executive Director of the Sustainable Energy Development Authority (SEDA) in New South Wales as a replacement for Cathy Zoi, the former Executive Director. Apart from the important role SEDA plays in the sustainable and renewable energy areas, SEDA is also providing the Key Centre with funding to assist in the development of various new courses that form part of the new undergraduate engineering degree. Another minor change to the membership of the Advisory Committee relates to the affiliation of Professor Martin Green who was originally a member in his capacity of Director of the PVSRC, but is now a member in the capacity of Director of the new Special Research Centre for Third Generation Photovoltaics which commenced in the year 2000. Key Centre Staff All of the full time and part time staff of the Key Centre are listed in the Key Centre structure on the previous page. Details of the new academic staff have been provided in the section on “Education”.

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Key Centre DirectorStuart Wenham

AdvisoryCommittee

ManagementCommittee

AdministrativeOffice

ManagerLisa Cahill

Businessand Operations

ManagerMark Silver

FinancialOfficer

Julie Kwan

OH&S ChairMark Silver

Education andPromotion Officer

Robert LargentAdministrative

SupportJenny HansenJenny Noble*Anja Aberle

Tanya Gately

SafetyCo-ordinator

Alistair Sproul

ComputerSystems

and ProgrammingLawrence Soria

Anna Bruce

TeachingLaboratory

Gordon Bates

Education Collaborative Research

Undergrad.Programs

C.B. Honsberg

Postgrad.Programs

S.R Wenham

OtherEducationR. Largent

CourseDevelopment

A. BruceC.B. Honsberg

J. CotterA.G. AberleA.B. Sproul

M. WattM.A. Green

S.R. WenhamR. Simms**

Project 1.1BP Solar

S.R. Wenham/C.B. Honsberg

Project 1.2Eurosolare

C.B. Honsberg

Project 1.3Topsil

J. Cotter

Project 1.4BP SolarJ. Cotter

Project 2.1Pacific SolarP.A. Basore/A.B. Sproul

Project 3.1Pacific SolarE. Spooner/

S.R. Wenham

Profect 5.1ACRE

M. Watt

* Administrative Office Manager while Lisa Cahill is on maternity leave** Contracted from Massey University, New Zealand

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Postgraduate Research Students The list of postgraduate research students supervised by the Key Centre staff are as follows : Linda Koschier (PhD) Bradley O’Mara (PhD) Keith McIntosh (PhD) Oliver Nast (PhD) Anita Ho (PhD) Peter Cousins (PhD) Alexander Slade (PhD) Bryce Richards (PhD) Anna Bruce (PhD) Nicholas Shaw (PhD) Bernhard Vogl (ME) Andrew Brown (PhD) Stephen Pritchard (PhD) Steven Bremner (PhD) Faruque Hossain (ME) Ajmal Beg (PhD) Eun Chel Cho (PhD) Didier Debuf (Part-time PhD) Jiun-Hua “Allen” Guo (PhD) Daniel Krcho (PhD) Kuo-Lung “Albert” Lin (PhD) Attachai “Tao” Ueranantasun (PhD) Dirk-Holger Neuhaus (PhD) Per Widenborg (PhD) Johnny Wu (PhD)

From the above list of postgraduate research students, the first four have completed their PhD work during the year 2000 and submitted their theses. The first of these, Linda Koschier, focussed her work on project 1.1, the collaborative research project with BP Solar. The second student, Bradley O’Mara, focussed his PhD research in the area of project 3.1 with Pacific Solar. The third of the PhD students, Keith McIntosh, made significant contributions to project 1.2 with Eurosolare during his thesis work and in fact spent several weeks in mid-2000 carrying out some of his PhD research in the facilities of Eurosolare in Rome. The work of the fourth PhD student Oliver Nast was related to the activities of Pacific Solar and encompassed by project 2.1. Not all of the PhD students listed above focus their PhD research activities in the collaborative research areas encompassed by the projects listed in the Key Centre structure on the previous page. A significant portion of the work carried out is less commercially oriented and more academic in nature, but with the projects still supervised by the Key Centre academics.

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9. KEY CENTRE ACTIVITY PLAN FOR 2001

Attachment 1 contains a summary of the Operational Plan for the Key Centre for Photovoltaic Engineering in 2001, which was prepared and presented to the Dean of the Faculty of Engineering. In addition, the Key Centre activities for 2001 have been documented under each of the relevant sections in this report and to a lesser extent in the accompanying general Key Centre report. The following summarizes these proposed activities for 2001. Teaching (i) Master of Engineering Science in Photovoltaics and Solar Energy The new Master of Engineering Science in Photovoltaics and Solar Energy will be submitted for approval in 2001 to the School, Faculty of Engineering, Academic Board and eventually the University Council. Gaining approval at each of these levels will undoubtedly require further development and refinement of various aspects of the proposal. (ii) Undergraduate Degree At undergraduate level, with the Key Centre having successfully launched the new undergraduate degree in Photovoltaics and Solar Energy in the year 2000, Key Centre academics will be involved in teaching the first year and second year students of this program during 2001. At present, the teaching load is not high for the Key Centre academics but will increase year by year until the targeted level of 12 units of credit teaching per year per academic is reached. (iii) PhD and Project Supervision In addition to course work teaching, the Key Centre academic staff will continue with PhD and undergraduate project supervision. These activities will also progressively increase during 2001 and subsequent years as postgraduate and undergraduate enrolments increase and as new Key Centre staff are appointed.

(iv) Internet Courses The Key Centre will continue to offer internet based courses during 2001 which attract enrolments from many countries around the world. These courses are offered in collaboration with ACRE with the next course being the Applied Photovoltaics scheduled for delivery in September 2001. (v) High School Lectures Other educational activities planned for 2001 include the delivery of 32 lectures to 1,600 Year 12 high school students on the topic of innovation. These lectures are to be delivered at the Power House Museum in late February/early March. These lectures are presented annually and provide an excellent opportunity for disseminating information and teaching about renewable energy technologies and photovoltaics to large numbers of high school students and their teachers. These lectures are organised by the Office of the Board of Studies, New South Wales and are offered annually. Accompanying notes are also produced and published by the Board of Studies, providing high school students with the opportunity to study photovoltaics and renewable energy technologies as case studies in innovation for their higher school certificate. Course Development The process of developing new courses for the new undergraduate program and Master of Engineering Science program will continue during 2001 and subsequent years. Key Centre academics spend a significant portion of their time at present on course development with appropriate support from our education officer, administrative staff and computer programmer who is experienced in the development of multi-media presentations. The schedule for new course development is shown in Table 1 which indicates the course being developed, its scheduled completion date, the first time the course will be offered, and the academic staff member taking responsibility for the course and its development. The courses to receive most emphasis during 2001 are those listed in the attached 2001 Operational Plan for the Key Centre.

35

For some existing courses, ongoing development will also be necessary to both update material and in some cases adapt the material to suit distance learning via web based teaching. Commercialisation and Technology Transfer The next stage in the technology transfer to technicians and researchers from Eurosolare will commence in late February 2001. At least one Key Centre staff member will visit Eurosolare later in 2001 to ensure that effective transfer and implementation has taken place. With other companies interested in licensing Key Centre technology, it is anticipated that further training and technology transfer will need to be scheduled for later in 2001. Research Activities The various industry collaborative research projects involving the Key Centre have been described in detail under the heading of "Research". These projects continue during 2001 in accordance with the documented expected outcomes and performance measures also listed in the Research Section. Particular emphasis will be placed on the development of the two new collaborative projects with Topsil and BP Solar. Various other companies have indicated an interest to commence negotiations with the Key Centre to also establish collaborative research projects in the future. These plans and negotiations will progress during 2001. Promotion A summary of the planned marketing and community outreach activities is provided in the attached 2001 Operational Plan for the Key Centre for Photovoltaic Engineering. However, following the demonstrated success of the undergraduate degree program in attracting high quality students, the importance of promotion and marketing during 2001 is reduced. Nevertheless the Faculty of Engineering at UNSW has an extensive program of marketing and promotion for all of the

engineering degrees, with the Key Centre staff participating in all of the corresponding activities. These include various information days and information nights in a range of locations and the provision of demonstrations and information desks at events such as the UNSW Open Day, and at special activities surrounding the Solar Car Project and SUNSPRINT, the state-wide model solar car race for high school students. The Key Centre also makes extensive use of its website for dissemination of information relating to the Key Centre activities and in particular the educational programs. The Key Centre also has information packs for distribution to those inquiring about the Key Centre educational programs with the packs including a range of material and information sources including a CD-Rom produced specifically for the provision of information about the new Engineering Degree in Photovoltaics and Solar Energy. Sustainability Of particular importance in all Key Centre activities is the objective to become self-sustaining by the end of the six years of ARC funding for the Key Centre. The pursuit of this aim has had significant impact on activities during the first two years of Key Centre operation, with the emphasis being to develop activities and income sources that would enable the Key Centre as a whole to be self-funding. This emphasis will continue during 2001, with the only activities planned being those judged to have the potential to become self-funding in the long-term. The existing collaborative research programs with industry have already demonstrated their self-sustainability with no ARC funds to be spent on these projects during 2001. In contrast, substantial levels of Key Centre ARC funding has been spent in employing staff and developing new courses and teaching materials for the new undergraduate Engineering Degree in Photovoltaics and Solar Energy and the new Master of Engineering Science in Photovoltaic Engineering. The investment in these activities will continue during 2001 with the expectation that in several years, these educational programs will be

36

self-supporting by generating sufficient income to fund both the staff and teaching materials and running costs necessary to offer these programs indefinitely. At present, without the ARC funding and the host institution support, the Key Centre activities fall short of being self-sustaining by approximately $600,000 per annum. However, with the new program's demonstrated ability to attract the required numbers of high quality students, in three more years, the Key Centre is estimated to be able to attract an additional income of $500,000 per annum through EFTSU’s' with the other $100,000 in difference being able to be saved through reduced annual expenditure on teaching laboratory and course material development. Teaching Laboratory Development The development of the new Photovoltaics Teaching Laboratory will continue during 2001 with the design and implementation of a range of new sets of experimental apparatus. These will include the installation of a range of grid connected photovoltaic modules each with its own inverter and monitoring circuitry. Other equipment will include photovoltaic powered water pumping systems, battery charging, systems for studying and evaluating mismatch effects in solar

modules, experiments for measuring and analysing thermal performance of photovoltaic module encapsulation, various solar simulators, hybrid photovoltaic systems, etc.. The first of these experimental setups is scheduled for completion by the end of May, 2001 in readiness for student experiments in the course SOLA3540. As an extension of the Teaching Laboratory, computing facilities are also being established during 2001 to provide an environment for the students in which to study and use computer modelling and computer-aided design packages. Some of these computers will also be networked to provide students with internet access. Other computers will be used for controlling and monitoring student experiments such as for monitoring the performance of each individual solar module and its corresponding inverter in each of the grid-connected systems. Both the photovoltaics Teaching Laboratory and the corresponding Computer Laboratory are targeted for completion by the end of 2001 in readiness for full scale use when the present second year students commence the third year of their program.

37

ATTACHMENT 1 : 2001 School Operational Plan The following documentation relating to the Operational Plan for the Key Centre for Photovoltaic Engineering in 2001, was prepared and presented to the Dean of the Faculty of Engineering. Major Goals/ PREP area

Action planned/ implementation Source of Funds Staff responsible

Performance measure Priority

Teaching Development of photovoltaics teaching laboratory + range of new experimental hardware set-ups (EE417) Development of computer lab for teaching (EE416) Commence the development of new courses: SOLA2020 SOLA5050 SOLA2060 SOLA3055 SOLA5052 Development of a range of second year student projects

Key Centre/Op Grant Key Centre/Op Grant Key Centre/Industry Key Centre/Industry Key Centre Key Centre/Op Grant Murdoch University Key Centre/Op Grant

S. Wenham, M. Silver, G. Bates L.Soria, M.Silver, S. Wenham S. Wenham C. Honsberg A.Sproul J. Cotter A.Sproul/M. Watt J. Cotter + all staff

Functional laboratory able to accommodate student experiments Functional laboratory able to accommodate student needs Implementation + student survey Implementation + student survey Implementation + student survey Implementation + student survey Implementation + student survey Implementation + student survey

High Med High Med High Low Med High

38

Human Resources

Sharing of some administrative functions with one or more other schools. To be implemented through negotiation.

NA HOS Reduced administrative work loads Med

Research Appoint an academic staff member to the position of safety co-ordinator for the research labs, facilitating his commitment of 25% of his time to this task. Resourcing safety upgrades and safety requirements in the research labs. Seek funding. Clearly identify a staff member responsible and in control of each area of the laboratories Recommissioning of equipment in 229 Apply for large ARC Discovery Grant covering the work of all academics

Operating grant ??? NA Industry/RIBG/Op grant/Capital grant ARC

HOS All staff in control of lab facilities HOS J. Cotter/ M.Silver HOS

Performance review Review by OH&S committee Produce report Functioning laboratory Submission of grant application

High High High Med High

Marketing & community outreach

Participation in the Office of the Board of Studies NSW annual lectures at the Powerhouse Museum involving 1600 students from about 100 schools

Board of Studies

S. Wenham/ R. Largent

Presentation of lectures + teacher evaluations

Med

39

Participation in Faculty of engineering marketing and promotion activities Organise a Renewable Energy Symposium for high school students Organise the NSW model solar car race SUNSPRINT for high school teams Promote and run the virtual world solar challenge Prepare, publish and print science booklet to accompany the “Hands and Minds” video in distribution to all NSW high schools

Fac of Eng Australian CRC for Renewable Energy Fac of Eng/Key Centre/Industry Key Centre/Industry Fac of Eng/Key Centre

Lisa Cahill/ HOS HOS/M.Silver/J. Noble R. Largent J. Cotter R. Largent

Reviewed by faculty Implementation of symposium and attendance by high school students Running of the event and participation by high school teams Number of entries Successful distribution to all high schools in NSW

High Med Med Low High

International-isation and strategic alliances

Develop or continue to develop various strategic alliances and collaborations such as with Loughborough University (UK), Oregon Institute of Technology (US), Murdoch University (WA), Massey University (NZ), Georgia Institute of Technology (US), plus a large number of companies internationally.

Industry, Key Centre, other institutions, Op grant

S. Wenham, C.Honsberg, J.Cotter, M.Silver

Each collaboration has its own performance targets and expected outcomes.

High/ Med/ low

40

New Academic Programs

Development of MEngSci in Photovoltaics and Solar Energy for implementation in 2002 Development and implementation of BE in Renewable Energy Engineering similar to the one established at Murdoch Uni under the co-ordination and direction of our staff. This program will use the courses jointly developed by UNSW and MU. Development of various new double degree options based on the most popular combinations of our 1st and 2nd year students

Key Centre Key Centre/ Industry Key Centre

HOS, Director of academic studies HOS, Director of academic studies HOS, Director of academic studies

Target enrolment of 10 students in 2002, 12 students in 2003, 15 students in 2004 Approval of Academic Board/University Council. Target enrolment of 20 students in 2003, 25 students in 2004, 30 students in 2005 Identification of appropriate combinations; development of proposals; approval of Academic Board/University Council.

High Med Med

Resource Management

Regular HOS Advisory committee meetings for making decisions on resource management. See plans for establishing space owners within the research labs listed under “research” See teaching lab development under “teaching” See computer lab development under “teaching”

NA HOS Minutes of meetings High

41

Financial Plan

The PV Centre financial plan and strategy is as documented in the Key Centre for PV Engineering Proposal endorsed by the ARC and UNSW when establishing the Key Centre in 1999. The main focus is on becoming self sustaining by the end of the 6-year ARC funding period. For 2001: EXPENDITURE Academic Salaries ($600k) Technical Support staff ($360k) Admin staff ($260k) Equipment ($500k) Industry collaborative research ($450k) Research projects ($1 million) Teaching Lab development ($300k) General running costs ($100k)

Op Grant/Key Centre Key Centre/Op grant/ARC Key Centre/Op grant Capital grant/Op grant/Key Centre/ Industry/RIBG Industry/ARC ARC/Royalties Key Centre/Op grant/industry Key Centre/Op grant

42

INCOME Op Grant ($650k) Key Centre+host inst ($550k) SRC+host institution ($600k) Industry ($250k) SPIRTS ($300k) Royalties etc ($300k) Other ARC ($500k) Capital grant ($300k) RIBG ($100k) Other ($100k)

43

ANNUAL

REPORT

2000

PHOTOVOLTAICS

SPECIAL RESEARCH

CENTRE

Annual Report

2000

PPHHOOTTOOVVOOLLTTAAIICCSS SSPPEECCIIAALL RREESSEEAARRCCHH

CCEENNTTRREE

UNSW

The University of New South Wales

Centre for Photovoltaic Engineering Electrical Engineering Building

The University of New South Wales UNSW SYDNEY NSW 2052

AUSTRALIA Tel +61 2 9385 6001 Fax +61 2 9385 5412

E-mail: pv.labs@unsw.edu.au http://www.pv.unsw.edu.au

2

3

Table of Contents

Directors Report ........................................ 4 Staff ............................................................. 6 Facilities & Structures ................................ 8 Research Reports ....................................... 10 High-Efficiency Cell Group ...................... 10 Buried-Contact Solar Cell Group ............. 13 Thin-Film Cell Group ............................... 18 External Contacts ...................................... 25 Financials ................................................... 26 Publications .............................................. 27

4

The Photovoltaics Special Research Centre (PVSRC) is a Special Research Centre of the Australian Research Council (ARC). It was es-tablished at the University of New South Wales (UNSW) in Sydney in 1991 under the directorship of Prof. Martin Green and has received considerable fun-ding (A$ 8.8 M) from the ARC’s Special Research Centres scheme over the maximum funding period of nine years. The Centre’s broad aims and mission are “to accel-erate the development of photovoltaics (PV) as a sus-tainable energy source for large-scale use and to strengthen Australia’s al-ready strong base in PV research, manufacturing and applications". The ARC funding enabled the Centre to establish an international reputation of excellence in the area of bulk and thin-film silicon solar cells. Under the leadership of Professors Martin Green and Stuart Wenham, numerous new silicon solar cell world records were achieved, promising new solar cell technologies have been developed and transferred

into the PV industry, and a University spin-off com-pany (Pacific Solar Pty. Ltd.) has been established off-campus to commercial-ise the Centre’s patented parallel multijunction thin-film silicon solar cell con-cept. This spin-off com-pany is one of the largest investments (about A$ 50 M) in renewable energy in Australian history, as well as one of the Nation’s largest ever university-industry commercialisation projects. At the end of 1999, Founding Director Prof. Martin Green resigned from the directorship of the Centre to take up the directorship of the new Centre for Third Gener-ation Photovoltaics at UNSW. In addition to this new ARC Centre, the ARC approved the continuation of the Photovoltaics Spe-cial Research Centre and its cutting-edge research, however, without support from the ARC’s Special Research Centres scheme. Prof. Green’s role has jointly been taken over by the new Directors, Associ-ate Professor Armin Aberle, Associate Professor Chris-tiana Honsberg, and Dr.

Jianhua Zhao. They are responsible for continuing the Thin-Film Cell, Buried-Contact Cell, and High-Efficiency Cell strands of the original Centre, respec-tively. In it’s “new phase of life”, the Centre’s acti-vities rely on income from a variety of sources, such as competitive research grants and royalties. As described in this Annual Report, in 2000 the Centre has continued to deliver world-class research results in the above-mentioned three strands. Particular highlights are: • The 21.1% efficiency

for a PERT cell on an n-type CZ Si substrate (which is a new world record for such CZ Si), and the 21.9% efficien-cy for a PERT cell on a gallium doped p-type CZ Si substrate (which is the second highest efficiency ever reported for gallium doped CZ Si),

• the demonstration of

several new key capabi-lities of titanium dioxide (TiO2) dielectric coat-ings (incl. high-temper-ature/high-lifetime pro-cessing, front surface

DIRECTORS REPORT In 2000, the Photovoltaics Special Research Centre entered a “new phase of life” without direct support from the Australian Research Council.

5

passivation, diffusion masking), and the successful transfer of the buried-contact solar cell technology to a group of 26 UNSW undergrad-uate engineering stu-dents who made over 3000 high-efficiency solar cells for their solar-powered race car, and

• the achievement of

high-quality epitaxial growth of large-grained polycrystalline silicon (“poly-Si”) films on glass at low temperature (~600°C) by ion-assisted deposition.

In 2000, Centre staff have been able to secure a range of competitive research grants from the University, the ARC and other sources, providing the financial basis for the Centre’s continuation in the near term. Needless to say, experimental research is expensive and hardly ever self-funding, putting enormous pressure on Centre staff to continuously look for additional funding opportunities. May we take this oppor-tunity to thank all those who have contributed to the continuing success of

the Centre in 2000. Photo-voltaics is in an exciting phase of growth, and pos-sibly our contributions to the field may help to some small extent to maintain our precious planet Earth a green and livable place.

A/Prof. Armin Aberle A/Prof. Christiana Honsberg Dr. Jianhua Zhao Director Thin-Film Cells

Director Buried-Contact Cells

Director High-Efficiency Cells

6

DIRECTORS Fig. 1

Thin-Film Cells: Armin G. Aberle*, Dipl.-Phys. (BSc, MSc), PhD (Freiburg, GER), Dr. habil. (Hannover, GER), MIEEE, MDPG ∗ Buried-Contact Cells: Christiana B. Honsberg*, BEE, MSc, PhD (Delaware, USA) High-Efficiency Cells: Jianhua Zhao, ME, PhD (UNSW), MIEEE

AFFILIATED ACADEMIC STAFF Jeffrey E. Cotter, BEE, MSc, PhD (Delaware, USA) Martin A. Green, BE, MEngSc (Qld.), PhD (McMaster, CAN), FAA, FTS, FIEEE, FIEAust Gernot Heiser, BSc (Freiburg, GER), MSc (Brock, CAN), PhD (ETH Zurich, CH), SMIEEE, MACM Stuart R. Wenham, BE, BSc, PhD (UNSW), FTS, SMIEEE (also Head, Centre for Photovoltaic Engineering)

BUSINESS & TECH-NOLOGY MANAGER Mark D. Silver*, BE (UNSW), GMQ (AGSM) (also Leader, Laboratory Development and Operations Team)

FINANCIAL CLERK Julie Kwan*

∗ Full-time involvement with the Centre for Photovoltaic Engineering. Part-time to this Centre.

RESEARCH AND ENGINEERING STAFF Project and Senior Project Scientists: Aihua Wang*, BE (Nanjing, China), PhD (UNSW) Professional Officers: Gordon Bates*, BA Ind.Des. (UTS) Martin Brauhart*, BE (UNSW) (on leave 05/00 to 11/00) Hamid R. Mehrvarz*, BE (Univ. of Science & Technology, Iran), ME (Univ. of Tarbiet Modarres, Iran), PhD (UNSW) Lawrence Soria*, Assoc. Dip. Comp. Appl. (Wollongong) Jules Z.S. Yang*, BSc (Eastern China Normal University, China) Technical and Senior Technical Officers: Tim Seary* Laboratory Assistant: Claudia Harder (since 9/00) (P/T)

RESEARCH FELLOWS/ ASSOCIATES Pietro P. Altermatt*, Dipl.-Phys. (BSc, MSc), PhD (Konstanz, GER) Robert Bardos*, BSc (Hons) (Melbourne) Patrick R. Campbell*, BSc, BE, PhD (UNSW) Richard Corkish*, BE (RMIT), PhD (UNSW) Ximing Dai, BSc (Zhejiang, China), PhD (UNSW). Mark J. Keevers*, BSc, PhD (UNSW) Tom Puzzer, BSc, PhD (UNSW) (P/T) David Roche*, BE, BA (UNSW). Wolfgang Honsberg, Dipl.-Chem. (BSc, MSc), PhD (GER).

Fig. 1: Nils-Peter Harder, Eun-Chel Cho, Dirk-Holger Neuhaus and Per Widen-borg working on the Centre’s ion-assisted deposition machine for silicon on glass.

STAFF

7

VISITING RESEARCH FELLOWS/ASSOCIATES Lukas Feitknecht, BE (Neuchatel, CH) (03/00 - 08/00) Nils-Peter Harder*, Dipl.-Phys. (BSc, MSc) (Leipzig, GER) Ralph Kuehn, Dipl.-Phys. (BSc, MSc) (Konstanz, GER) (01/00 - 06/00) Andreas Schenk, Dipl.-Phys. (BSc, MSc), PhD (Berlin, GER), Dr. habil. (Zurich, CH) (02/00 - 03/00) Dengyuan Song, BSc, MSc (Hebei, China) (since 10/00)

Fig. 2

HIGHER DEGREE STUDENTS

Fig. 3 Masters Faruque Hossain, BSc, MSc (Dhaka, Bangladesh), MEngSc (UNSW) Bernhard Vogl, BE (FH Regens-burg, GER)

Doctoral Ajmal Beg, BE (Kyoto, JPN) (since 03/00) Stephen P. Bremner, BSc (UNSW) Eun Chel Cho*, BE, ME (Kwang-woon, South Korea) (since 7/00) Didier Debuf, BE, ME (UNSW) (P/T)

Jiun-Hua “Allen” Guo, BSc, MSc (National Taiwan University, Tai-wan) Linda Koschier*, BE (UNSW) (until 09/00) Daniel Krcho*, RNDr (Bratis-lava, Slovakia) (also P/T Profes-sional Officer) Kuo-Lung “Albert” Lin*, BE (Tat-ung, Taiwan), MSc (Liverpool, UK) (since 03/00) Keith R. McIntosh*, BSc (Sydney) Dirk-Holger Neuhaus*, Dipl.-Phys. (BSc, MSc) (Hannover, GER). Bradley O’Mara*, BSc EET (Ore-gon Tech, USA)

Stephen Pritchard*, BA, BE (UNSW) (until 08/00) Bryce Richards*, BSc (Welling-ton, NZ) Nicholas C. Shaw*, BE (UNSW) Alexander M. Slade*, BSc (Monash) Attachai Ueranantasun, BE (KMUTT, Thailand) MEngSc (UNSW) Per Widenborg*, BSc, MSc (Stockholm, SWE) (since 01/00) Johnny Wu*, BE, BSc (Qld.)

UNDERGRADUATE THESIS STUDENTS Khairil Anwar Boon Hee “Winston” Chin Peter Cousins Mu-Fen “Kenney” Huang Teck Hui “Ryan” Oh Glen Preema Chee Bon “James” Tan

VISITING UNDER-GRADUATE STUDENT * Manfred Fahr (FH Efflingen, GER)

* Full-time involvement with the Centre for Photovoltaic Engineering. Part-time to this Centre.

Fig. 3: High-efficiency group meeting with Ximing Dai, Aihua Wang, Martin Green and Jianhua Zhao.

Fig. 2: Manfred Fahr, Hamid Mehrvarz, Peter Cousins and Bryce Richards discussing TopCell project samples.

8

Laboratory Development & Operations Team Laboratory Manager: Mark Silver (group leader) Professional Officers: Gordon Bates Martin Brauhart Dr. Daniel Krcho Lawrence Soria Jules Z.S. Yang Technical Officer: Tim Seary Solar Cell Fabrication Labs The Centre is physically located on UNSW’s Kensington Cam-pus, about 6 km southeast of Sydney’s Central Business Dis-trict (see Fig. 4). Organisation-ally, the Centre is located within the Centre for Photovoltaic Engineering within the Faculty of Engineering. The Centre has access to the laboratories of the encompassing larger Centre, most importantly the three solar cell fabrication labs (high-effi-ciency cells, buried-contact cells, thin-film cells) and the device characterisation area. The three cell fabrication labs cover a floor space of about 480 m2. They are located on three floors of the School of Electrical Engineering building (see Fig. 5) and are serviced with filtered and conditioned air, cooling water, processing gases, de-ion-ised water supply, chemical fume cupboards and exhausts.

There is an additional area of about 200 m2 next to the labs for the accommodation of staff, re-search students and lab support facilities. Off-campus areas of 200 m2 are used for the storage of chemicals and spare parts.

COOGEE

MAROUB RA

KENSINGTON

UNIVERSITY OFNEW SOUTH WALES

BONDI

SYDNEYAIRPORT

BOTANY

SYDNEY CBD

Paci fic SolarPty. Ltd.

Fig. 4: Centre location in Sydney.

The three solar cell fabrication labs are equipped with a range of processing and characteri-sation equipment, including 37 diffusion furnaces, 6 vacuum evaporation systems, 3 laser scri-bing machines, rapid thermal annealer, four-point sheet resis-tivity probe, quartz tube washer, metal plating units (nickel, sil-ver, copper), infrared and visible wavelength microscopes, 3 mask aligners, spin-on diffusion system, automated photoresist dual track coater, photoresist spinner, sputter system, reactive ion etcher, plasma-enhanced chemical vapor deposition sys-tem, glass texturing press, TiO2 spray deposition system, ion-assisted deposition system, and a laboratory control and data acquisition system.

Fig. 5

Fig. 5: Location of Centre facilities within the L-shaped Electrical Engineer-ing building.

FACILITIES & STRUCTURES The Centre has access to the facilities operated by the Centre for Photovoltaic Engineering. The Centre’s major work areas are three Solar Cell Fabrication Laboratories (High-Efficiency Cells, Buried-Contact Cells, Thin-Film Cells) and the Device Characterisation Area.

9

Device Characterisation Area Space in the basement of the Electrical Engineering building was made available to the Centre by the University in 1995. The space contains a reception area, seminar room, library, offices for centre staff interacting with the public and industry (including the Business & Technology Manager), com-puter workstations for the device modelling activities of the Cen-tre, and the Device Characteri-sation Area. The Device Characterisation Area of 60 m2 houses charac-terisation equipment including “Dark Star” (a station for temper-ature controlled current-voltage measurements), a Fourier trans-formation infrared spectroscopy system, admittance spectroscopy system, ellipsometer, photocon-ductance decay equipment (detection by microwaves or in-ductive coupling), infrared microscope, spectrometer for transmission and reflection measurements, and a spectral response system. Semiconductor Nanofabrication Facility The Centre also has access to equipment within the Semicon-ductor Nanofabrication Facility (SNF) at UNSW. This is a joint facility of the Faculties of Engin-eering and Science and houses a microelectronics laboratory and a nanofabrication laboratory for e-beam lithography. The SNF

provides an Australian capability for the fabrication of advanced nanoscale semiconductor de-vices and their integration with microelectronics, using the latest techniques of electron beam patterning and scanning probe manipulation. The SNF includes facilities for both the fabrication and mea-surement of advanced semicon-ductor nanostructures. It fea-tures two class-3.5 clean rooms and two adjacent “grey areas” of class-350 conditions. The ground floor clean room houses an EBL 100 Nanolithography system, together with UV align-ers, metal evaporators and related semiconductor pro-cessing infrastructure. The first-floor clean room and grey areas

house a complete Si microelec-tronics process line, including plasma etching and CVD depo-sition facilities. Extensive gas handling systems for a full in-ventory of Si and GaAs process gases are available. Other Facilities

Fig. 6 Additional equipment is avail-able on the University campus, which is commonly used for cell work. Included in this category are electron microscopes (scann-ing, transmission), focussed ion beam microscopes, X-ray defrac-tion, surface analysis, and photoluminescence equipment.

Fig. 6: Jianhua Zhao processing highest-efficiency silicon wafer solar cells.

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High-Efficiency Cell Group

Senior Project Scientist: Dr. Jianhua Zhao (group leader) University Staff: Prof. Martin Green Prof. Stuart Wenham Project Scientist: Dr. Aihua Wang Research Fellow: Dr. Pietro Altermatt Dr. Ximing Dai The aim of the high-efficiency cell group is to achieve conversion effi-ciencies as high as possible on the whole range of commercially available silicon wafer materials. The resulting improved understanding of silicon properties is expected to be beneficial for indus-trially relevant Si cells.

In 1999, the high-efficiency cell group demonstrated record ener-gy conversion efficiencies of 24.7% for a PERL (passivated emitter, rear locally diffused) cell made on a FZ (float-zone) sili-con substrate, and 24.5% effi-ciency for a PERT (passivated emitter, rear totally diffused) cell made on a MCZ (magnetically confined Czochralski) wafer. All these FZ and MCZ materials have excellent material quality with very low defect density, low oxygen content, and very high minority carrier lifetime.

However, these materials also are very expensive due to their complicated fabrication method. In 2000, the focus of the high-efficiency group shifted to lower-quality materials such as gallium-doped CZ [CZ(Ga)] and phosphorus-doped CZ [CZ(P)]. These wafers were supplied by Shin-Etsu Handotai Corp. (SEH), Japan, within a collaborative program. Another advantage of gallium-doped CZ wafers is that they avoid the performance degradation problem of boron-doped CZ silicon [CZ(B)]. Schmidt, Aberle and Hezel suggested in 1997 (Proc. 26th IEEE PV Specialists Conference, Anaheim, p. 13) that this degra-dation is due to the reaction bet-ween boron and oxygen, which are both present in substantial amounts in this material. They also showed that replacing boron by another dopant (such as Ga) solves the degradation problem of CZ silicon. 21.9% efficiency PERT cell on CZ(Ga) substrate

Fig. 7 The PERT cell structure is shown in Fig. 7. Compared to the pre-vious PERL cell, a light boron diffusion is added along the en-tire rear surface. The front and rear surfaces are both passivated

by a silicon dioxide film ther-mally grown at high temperature using trichloroethane (TCA). Surface recombination losses are further reduced by the light phosphorus and boron diffusions along the front and rear surfaces, respectively, suppressing the minority carrier densities. In the past, the boron diffusion used to cause increased surface recombination (and hence a re-duced open-circuit voltage) for cells made on FZ wafers from Wacker, Germany. However, when using the SEH materials, it was found that a boron diffusion at the rear surface generally im-proved the performances of PERT cells. Another advantage of the PERT cell structure over the previous PERL structure is its lower series resistance resulting from the full-area rear boron diffusion. The rather high series resistance of PERL cells (due to the local rear point contacts) limited their substrate resistivity to values below 2 Ωcm. In the case of PERT cells, however, resistivities as high as 5-10 Ωcm can be used, improving the performance due to a higher short-circuit current. PERT cells also perform better than PERL cells under concentrated sun-light, which is due to the lower series resistance.

n+ nhigh resistivity p-silicon

thin oxide (~200Å)

oxiderear contact

finger "inverted" pyramids

p+ p+

p+

double layerantireflectioncoating

p

p

Fig. 7: PERT (passivated emitter, rear totally diffused) cell structure.

RESEARCH REPORTS

11

PERT cells were fabricated on a whole range of SEH wafers: FZ(B), MCZ(B), CZ(B), CZ(Ga), CZ(In), CZ(Al), FZ(P) and CZ(P). Using photoconductance decay measurements, we found that CZ(Ga) wafers have very high and stable effective minority carrier lifetimes of up to 1.9 ms. PERL cells made on low-resis-tivity CZ(B) wafers showed a severe performance degradation during storage and the first few hours of illumination. However, all cells fabricated on the other substrates were stable. Table 1 shows the performance parameters of four PERT cells made on p-type CZ(Ga), CZ(In) and CZ(Al) substrates. Fig. 8 is the I-V curve of the CZ(Ga) sub-strate cell Ws11-3c measured at Sandia National Labs at 25ºC under the standard global AM1.5 spectrum (100 mW/ cm2). This cell has an efficiency of 21.9%, which is the second-highest efficiency ever reported for a cell made on a gallium-doped CZ wafer. The second cell Ws12-7d has a very high open-circuit voltage of 692 mV, which is 12 mV higher than the best-performing cell Ws11-3c. This is very close to the best Voc of 710 mV ever achieved at UNSW on textured p-type FZ(B) substrates. Unfortunately, this cell has a much lower fill factor and hence lower efficiency. It is believed that the open-circuit voltage is the most critical value to a Si solar cell technology, since it represents the total recombination occurring in the cell. Hence, 692 mV open-circuit voltage demonstrates the potential for significantly higher

cell performance in the near future, provided the fill factor problem can be solved.

Fig. 8 Cell Ws15-8a, made on a CZ(In) wafer, has a Voc of 674 mV and a marginally lower than expected efficiency after deposition of the antireflection coating. The CZ(Al) cells, which initially were thought to have the highest potential, performed rather poorly with a Voc of only 570 mV. Aluminium diffusion was commonly used in our previous PESC (passivated emitter solar cell) and LGBC (laser grooved buried contact) cell structures, and had produced Voc’s above 670 mV. It is presently not clear why Al doping during the crystal growth process gives a lower minority carrier lifetime than heavy Al diffusion. Stability study of CZ(Ga) cells

Fig. 9 The stability of the PERT cells on CZ(Ga) substrates was carefully

investigated. Two CZ(Ga) cells with different substrate resistivity were exposed to 1-sun illumi-nation. The result is shown in Fig. 9. It is seen that all tested CZ(Ga) cells have a stable per-formance during 15 hours of 1-sun exposure. The entire vari-ation in the cell’s Voc is within the measurement error of our test equipment. In contrast, a much larger degradation was observed for PERL cells made on CZ(B) substrates. 21.1% efficiency PERT cell on CZ(P) substrate Recently, we directed our research towards making high-efficiency solar cells on n-type CZ and FZ silicon substrates. Since CZ material is of much lower cost than our standard FZ material, it is of major commer-cial relevance. There are many advantages in using n-type silicon for high-efficiency cells, including:

Table 1: The performance of 4-cm2 PERT cells on SEH p-type CZ substrates. Cells Ws11-3c and Ws12-7d were tested at Sandia National Labs under the standard AM1.5 global spectrum (100 mW/cm2) at 25°C. The other two cells, which had no antireflection coating, were measured at UNSW without shading of the cell periphery and hence no efficiency values could be determined.

Cell name

Voc

(mV) Jsc

(mA/cm2) FF (%)

Effic. (%)

Growth method

Oxygen content (ppma)

Resistivity (Ωcm)

Wafer thickness (µm)

Ws11-3c 680 41.0 78.6 21.9 CZ(Ga) 19.0 5.3 200

Ws12-7d 692 40.5 75.9 21.2 CZ(Ga) 19.0 5.3 200

Ws15-8a 674 39.5 78.4 CZ(In) 16.4 14.5 300

Ws15-4b 570 27.0 80.2 CZ(Al) 17.7 0.73 300

0.0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8

volts04/11/00 7:27 AMWs11-3C

Re-measure with reference cell and test cell masked

25.1 °C0.9923 M*1.0000 S*

4.0 cm2

679.9 Voc(mV)566. Vmp(mV)

40.95 Jsc(mA/cm2)0.164 Isc(A)0.155 Imp(A)

0.786 FF21.90 % Eff

AM1.5GONE SUN

Fig. 8: The I-V curve of CZ(Ga) substrate cell Ws11-3c measured at Sandia National Labs under the standard AM1.5 global spectrum (25°C, 100 mW/cm2).

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• Higher carrier lifetimes have been demonstrated in n-type substrates, including FZ(P) and CZ(P) materials.

• Avoiding boron in CZ sub-strates may result in higher stable cell efficiencies. This is particularly important since the same low-cost CZ growth method can be used.

• For the same substrate resisti-vity, lower doping levels are needed in n-type cells, due to the higher carrier mobility in such substrates. This may also be one of the reasons for higher lifetimes in n-type substrates of the same resis-tivity compared to p-type material.

• n-type substrates have an ad-vantage over p-type substrates for concentrator cells. The Dember effect (i.e., the voltage drop in the base of the cell due to the non-equal mobility of electrons and holes) is expected to give a Voc gain in n-type cells and a Voc loss in p-type cells. The voltage gain in n-type cells is particularly enhanced under concentrated light and for higher-resistivity substrates.

• Using n-type wafers for con-centrator cells will also avoid the current sub-linearity prob-lem found in higher-resistivity p-type cells.

• n-type CZ wafers with phos-phorus diffusions on both sides have demonstrated very high and stable carrier life-times of up to 5 ms. This is comparable to the carrier life-times of p-type FZ substrates. The early experiments used the PERL structure for these n-type CZ cells. They gave a low Voc of below 630 mV, which was due to surface passivation problems. With the PERT cell structure, these problems are eliminated.

Table 2 shows the performances of two PERT cells on SEH n-type phosphorus doped CZ(P) sub-strates. Both cells have an effi-ciency of 21.1%, which is the highest efficiency ever reported for a solar cell made on an n-type CZ silicon substrate. The second PERT CZ cell has a very high Voc of 687 mV. Unfor-tunately, both cells have a rather low fill factor around 75%, an indication of processing related problems. Again, since Voc is the

most important parameter for a Si solar cell technology, these results show that n-type CZ(P) material has an efficiency potential of about 22.4%, pro-vided the fill factor problems can be eliminated. Assessment of free carrier mobility in silicon The literature offers many publi-cations on measurements of the free carrier mobility in silicon. However, if plotted in a single graph, the measured values scatter significantly. We found that most of the scattering arises from the fact that different authors made various assump-tions. The collection of data appears far more precise if the data is re-interpreted with con-sistent assumptions. For exam-ple, the influence of both the so-called Hall correction factor and incomplete ionisation of dopants can be clearly distinguished in the revised data set. We found that the mobility due to phonon interaction (a fundamental val-ue) is higher in high-purity FZ material than in CZ material. The reported differences in mobility between arsenic and phosphorus doped silicon is found to be merely a mirage arising from the various assump-tions that different authors made when representing their data. In device simulations, empirical mobility models are used as a function of dopant density instead of free carrier density. This causes deviations of up to 40%, especially in the doping range of many thin-film cells.

650651652653654655

0.1 1 10 100One-Sun Exposure Time, hour

Voc

, mV

Ws04-4c

Ws04-4e

692

693

694

695

696

0.1 1 10 100One-Sun Exposure Time, hour

Voc

, mV Ws12-3c

Ws12-3e

Fig. 9: Measured Voc of PERT cells made on CZ(Ga) substrates of (top) 5.3 Ωcm and (bottom) 9.1 Ωcm resistivity during 1-sun illumination.

Table 2: The performance of 4-cm2 PERT cells on SEH n-type CZ(Ph) substrates. Both cells were tested at Sandia National Laboratories under the standard AM1.5 global spectrum (100 mW/cm2) at 25°C.

Cell name

Voc

(mV) Jsc

(mA/cm2) FF (%)

Effic. (%)

Growth method

Oxygen content (ppma)

Resistivity (Ωcm)

Wafer thickness (µm)

Wn08-5a 679 41.2 75.5 21.1 CZ(P) 18 1.3 400

Wn08-1d 687 40.3 75.9 21.1 CZ(P) 0.4 400

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Buried-Contact Solar Cell Group University Staff: Dr. Jeffrey Cotter (group leader) Prof. Martin Green A/Prof. Christiana Honsberg Prof. Stuart Wenham Project Scientists: Dr. Ximing Dai Dr. Hamid Mehrvarz Research Fellows/Associates: Dr. Patrick Campbell Dr. Richard Corkish Dr. Wolfgang Honsberg Dr. Tom Puzzer David Roche Doctoral Students: Jiun-Hua “Allen” Guo Linda Koschier Keith McIntosh Stephen Pritchard Bryce Richards Nicholas Shaw Alexander Slade Attachai Ueranantasun Masters Students: Faruque Hossain Bernhard Vogl Undergraduate Thesis Students: Khairil Anwar Peter Cousins Visiting Student: Manfred Fahr The Buried-Contact Cell Group aims to develop new process technologies and device structures for commercially relevant silicon wafers. The group has a broad spectrum of research and development activities that address the evolving nature of commercial silicon wafers, which continue to im-prove both in terms of

quality and cost. As a result, the group seeks to develop new solar cell designs and processes that are well matched to the different types of wafers. The Group’s activities can be divided into general areas: the development of novel solar cell designs and fabrication processes based on the buried-contact technology, and the transfer of the buried-contact technology to industry collaborators. High-efficiency buried-contact solar cells

Fig. 10 One objective of the buried-contact cell group is to increase the efficiency of buried-contact (BC) solar cells without a sub-stantial increase in the cost of their fabrication. Research has concentrated on the double-sided buried-contact (DSBC) solar cell shown in Fig. 10. Devised at UNSW, this DSBC solar cell is capable of efficien-cies in excess of 20%. Experimental DSBC solar cells have demonstrated high short-circuit current densities and high open-circuit voltages since the early 1990s. In most cases, however, the fill factor of these DSBC solar cells was only in the

range 0.70 - 0.78, limiting the cell performance. Thus, research has focused on identifying the cause for the low fill factor. Several new characterisation techniques have been developed to analyse DSBC solar cells, including techniques to quantify the main factors limiting fill factor: shunting across the rear, floating-junction passivation layer, recombination associated with the rear n+-type layer, and recombination at the cell edges. The application of these new characterisation techniques, in combination with well-estab-lished techniques, has revealed that there exist several detri-mental mechanisms in a DSBC solar cell that can lead to a low fill factor: • shunting paths between the

rear n+-type layer and the p++-type silicon,

• significant contact resistance between the metal fingers and the p++-type silicon,

• localised Schottky contacts between the metal fingers and the p-type base,

• recombination at the edges of the solar cell, and

• recombination associated with the p++-type silicon–silicon dioxide interface.

Research is now aimed at alle-viating the influence of these detrimental mechanisms. The first three mechanisms have been eliminated in an improved DSBC fabrication procedure.

Fig. 10: Schematic of the double-sided buried-contact solar cell.

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Specifically, the time/temper-ature of the rear boron groove diffusion is increased and not followed by an oxidation step. This alteration prevents the occurrence of shunting and contact resistance associated with the p++-type silicon. Another important alteration to the DSBC fabrication procedure was the application of a longer drive-in time when forming the front n++-type diffused grooves. This alteration prevents the occurrence of localised Schottky contacts between the metal fingers and the p-type base. With these alterations, DSBC solar cells have been fabricated with a fill factor in excess of 0.78 (and 17% efficiency on untextured FZ wafers), but still below 0.80. Analysis of these devices reveals that if the last two detrimental effects listed above can be eliminated the fill factor can reach 0.82. Pigmented diffuse reflectors

Fig. 11 The buried-contact cell group is also developing a new type of reflector for enhanced light trapping in thin (150−200 µm) DSBC solar cells. Pigmented diffuse reflectors (PDRs) posses a structure similar to paint, where-by optically scattering particles (the pigment ) are suspended in an optically transparent medium (the medium ).

Fig. 12 Light scattered by the pigment travels through the medium and exits the reflector into the adjacent silicon layer. To pre-dict the increase in the short-circuit current generation of a light-trapping device with a PDR applied, the optical properties of the PDR, specifically the internal reflectivity (Rint ) and the effective refractive index (neff ), must be known. Two independent reflec-tion measurements of the PDRs external reflectance must be made — one in air (Rext-Air ) and a second with an intermediate thin

Si wafer (Rext-Si ). From the two independent measurements of external reflectance the values of Rint and neff can be extracted graphically (see Fig. 11), using optical models developed previously. Work is currently under way to develop and characterise new PDR materials that are speci-fically designed for light trapping in thin-wafer DSBC solar cells. Computer ray-tracing is being used to predict the maximum available current density of a silicon device with common textures and PDRs that have various properties. To this extent, work has determined (see Fig. 12) that the potential benefit of PDRs equals or betters either attached or detached metallic reflectors. This, combined with the potential low cost of these materials, makes PDRs an excellent candidate for enhanc-ing the performance of thin DSBC solar cells. The project

has attracted funding from industry, and the Group plans to apply for additional developmental funding under the Australian Research Council’s Linkages Scheme. Titanium dioxide coatings Novel applications for titanium dioxide (TiO2) thin films have the potential to reduce pro-duction costs of Si solar cells, especially for structures like the buried-contact cell. Several new uses for TiO2 films, deposited both by ultrasonic spraying and atmospheric pressure chemical vapour deposition (APCVD), are being investigated. Firstly, we have demonstrated by carrier lifetime measurements that the TiO2 film does not con-taminate the silicon wafer or furnace during lengthy high-temperature processing or laser scribing.

nEFF

RINT RINT(REXT-AIR,nEFF)

RINT(REXT-Si,nEFF)

Increasing RINT

Increasing nEFF

Fig. 11: The internal reflection and refractive index of a PDR can be determined graphically − at the intersection of the two curves Rint(Rext-Air, neff) and Rint(Rext-Si, neff).

37

38

39

40

41

42

0.0 0.2 0.4 0.6 0.8 1.0Broadband Reflectance

Max

imum

Lig

ht G

ener

ated

Cur

rent

Den

sity

(m

A/c

m2)

Detached Specular PDR (n = 1.0) PDR (n = 1.5)

PDR (n = 2.0) PDR (n = 2.5) PDR (n = 3.0)

Fig. 12: The maximum light-generated current density achievable for thin silicon solar cells with various types of pigmented diffuse reflectors (PDRs).

15

Secondly, we have demon-strated the growth of a thin silicon dioxide layer at the TiO2/Si interface by performing a brief oxidation after the deposition of the TiO2. Fig. 13 shows a cross-sectional scanning electron microscopy image of a typical film structure after the brief oxidation step. The thickness of the TiO2 is about 67 nm and the interfacial oxide layer is about 6 nm thick. X-ray photoelectron spectros-copy (XPS) was used to determine the chemical nature of the grown layer. In the XPS plot in Fig. 14, the surface of the TiO2 film is at t = 0 s, where the Ti:O ratio is about 1:2. Artefacts of the XPS measurement, namely preferential sputtering and islanding, make the SiO2 peak to be much broader than it appears to be in the SEM picture.

Fig. 13: SEM image (10° tilt) show-ing 67 nm of TiO2 and the ~6 nm interface layer grown during the brief oxidation.

Fig. 14

The interfacial SiO2 decreases the dark saturation current density J0e by nearly two orders of magnitude, from 4.1×10-12 A/cm2 (for TiO2 on bare Si) to 4.5×10-14 A/cm2 (measured under high-injection conditions). These results demonstrate the potential of TiO2 to provide a suitable level of electronic surface passi-vation. Thirdly, we have demonstrated the ability of using the TiO2 films as a phosphorus dopant source for emitter diffusion. Phos-phorus-containing compounds were added to the TiO2 pre-cursor and the deposited films

were subjected to the standard buried-contact emitter drive-in process. Initial results have shown that light diffusions to around 300 Ω/sqr. are possible. Finally, the applicability of TiO2 as a phosphorus diffusion barrier was investigated. Although the TiO2 acts suitably as a phos-phorus diffusion barrier, a reac-tion that occurs between phosphorus and TiO2 destroys the film's optical properties. The film also becomes conducting, and the resulting surface passivation is very poor. Laser-formed aluminium grid contact

Fig. 15 One conceptually simple method of forming a rear grid electrode is by laser-alloying aluminium and silicon using a programmable laser. The method is schematically shown in Fig. 15. In this process, a deposited layer or foil of alumin-ium is in close contact with the

rear surface of the solar cell while the laser beam melts the aluminium and silicon together in a localised region. By scanning the beam across the surface in a pattern of the grid, an alloyed rear contact grid can be formed by either melting (see Fig. 15a) or by melting and ablation (see Fig. 15b). One advantage of this technique is that intermediate dielectric layers, such as silicon dioxide or titanium dioxide, between the silicon and aluminium can be tolerated. This is because either the aluminium should reduce the dielectric when melted or melted/ablated. Such inter-mediate dielectric layers are useful for passivating the rear surface or as a mask for sub-sequent nickel-copper electro-less plating of the silicon-aluminium alloy groove. Furthermore, the aluminium covering the remainder of the rear surface can be used as a reflector or can be removed to form a transparent grid needed

0 1000 2000 30000

20

40

60

80

100

Co

nce

ntr

atio

n (

At.

%)

O Ti Si SiO

2

C

Sputtering Time (s) Fig. 14: XPS analysis chemically identifying that the interfacial layer is SiO2.

silicon-aluminiu m alloy

contact layer

silicon wafer(p-type)

silicon wafer(p-type)

evaporatedor foil

aluminium

laserlaser

(a) (b)

Fig. 15: (a) Melting and alloying to form an aluminium-silicon alloy layer and (b) melting and ablating the aluminium and underlying silicon to form a groove.

16

for PDR light trapping or bifacial operation. It is relatively easy to form a melted/ablated aluminium-silicon groove using either evaporated or foil aluminium; however, it is essential to use a vacuum stage to hold the aluminium foil in close contact with the silicon. Plating with nickel and copper is also straightforward (see Fig. 16), although it is necessary to have a suitable plating mask to pre-vent metal deposition across the whole rear surface. Silicon dioxide, silicon nitride and titanium dioxide have all been used successfully as plating masks in the standard buried-contact process.

Fig. 16: Side view (left) and top view (right) of a plated, laser-formed aluminium-silicon alloy groove.

An ohmic contact is readily achieved with the laser alloying process and buried-contact solar cells, although the specific contact resistance of plated grooves is relatively high in test structures. Standard buried contact solar cells fabricated on untextured 280 µm thick, p-type, 2.5 Ωcm FZ wafers have reached efficiencies over 15%, with little development or optimisation of the process. This project has attracted funding from industry, and the Group plans to apply for additional developmental funding under the Australian Research Council’s Linkages Scheme.

UNSW Sunswift II technology transfer

Fig. 17 UNSW’s Solar Car Racing Team is in the process of designing and building a new solar-powered race car for the upcoming 2001 World Solar Challenge. A team of 25 first-, second- and third-year under-graduate engineering students (PV, EE and MechE) plans to become the first solar racing team in the world to have built their own solar cells for their car. The project, called the TopCell Project after their gener-

ous industry sponsor, Topsil Semiconductor Materials, com-menced in mid-2000.

Fig. 18 The buried-contact cell group is providing technology and facili-ties, as well as training in cell processing. In addition, two postgraduate students and one professional staff member of the group worked for the students in particularly difficult or hazard-ous processes (e.g. wet chemical processing). On the whole, however, the majority of the production effort was carried out by the undergraduate students.

Fig. 17: Undergraduate students Jesse Clarke (foreground) and Lawrence Yu laser scribing the front metallisation grooves.

Fig. 18: Undergraduate students Esther Lee (left), Ly Mai (centre) and Ed Pink (far right) take notes on the aluminium evaporation process.

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The project was organised and managed by the undergraduate students, including logistics, process control and process engineering. In addition, the students carried laboratory operations responsibilities, for example, assisting with the maintenance of the DI water plant, the chemical stocks, the process gas supply, and the computer network. The first training stage focused on laboratory safety and processing skills and took just over three weeks, after which the operations were turned over to the students. The second training stage focused on process control engineering – it took just over five weeks to scale up to 100 wafers (i.e., 200 solar cells) per day and bring the process under control. The final training stage focused on process optimisation to bring the batch average efficiency from 18.5% up to 19.5%. By the completion of the project in early 2001, the students will have made almost 7500 solar cells, of which they will use the best 3000 for their car. The team hopes to sell the best of the remaining solar cells to one of their competitors and become the first ever team of university students to manufacture and sell a significant number of high-efficiency solar cells. Theory and modelling of quantum well solar cells

Fig. 19 Investigations are continuing into the potential for novel solar cell designs, such as the inclu-sion of quantum wells or quan-tum dots, to increase the theo-retical efficiency limits beyond those of homojunction solar cells. Quantum wells are very thin layers of one semiconductor sandwiched between layers of another, producing transport restrictions and quantisation of the energy band structure in one dimension. Quantum dots are

restricted and quantised in three dimensions. Monte Carlo device modelling methods are now being devel-oped for application to these problems. In Monte Carlo de-vice modelling, groups of charge carriers are represented by par-ticles whose movement through the device is affected by electric fields and scattering processes. Random numbers select the type and effect of scattering events in the simulations. The method effectively solves the fundamen-tal Boltzmann transport equation and allows the observation of carrier distributions through time. Additionally, it shows the behaviour of “hot” carrier popu-lations that do not have the “relaxed” energy distributions that are often assumed in device simulations.

Fig. 20

As a preliminary step, the Monte Carlo technique is being applied to a solar cell that includes an intrinsic region with a layer of material that is able to absorb light of longer wavelengths. The structure is similar to that of a double-heterostructure laser. Particles with position depen-dent weights (i.e. the number of electrons represented by each particle) are needed in order to reduce the statistical noise in lightly populated regions. A standard drift-diffusion device simulator is used to derive the initial particle distribution. Fig. 19 shows particles, each representing a group of elec-trons, evenly distributed across the device thickness. Carrier concentrations (Fig. 20) are de-rived from the particle distribu-tion and their weights.

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7

Position ( µµm)

108

109

1010

1011

1012

1013

1014

1015

1016

1017

1018

Carrie

r co

ncen

tration

(cm

-3)

Fig. 20: Carrier concentrations derived from the distribution of the particles and their weights.

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7

Position ( µµm)

-6.5

-6

-5.5

-5

-4.5

-4

-3.5

El

ec

tr

on

en

er

gy

(e

V)

Fig. 19: Energy band diagram and electron particle distribution in a forward biased double heterostructure in the dark.

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Thin-Film Cell Group University Staff: A/Prof. Armin Aberle (group leader) Prof. Martin Green Prof. Stuart Wenham

Fig. 21 Research Fellows/Associates: Dr. Pietro Altermatt Robert Bardos Dr. Patrick Campbell Dr. Mark Keevers Dr. Tom Puzzer Visiting Research Fellows/ Associates: Lukas Feitknecht Nils-Peter Harder Ralph Kuehn Dr. Andreas Schenk Dengyuan Song Doctoral Students: Ajmal Beg Eun Chel Cho Didier Debuf Daniel Krcho Kuo-Lung “Albert” Lin Dirk-Holger Neuhaus Per Widenborg Johnny Wu Undergraduate Thesis Students: Boon Hee “Winston” Chin Mu-Fen “Kenney” Huang Teck Hui “Ryan” Oh Glen Preema Chee Bon “James” Tan The primary aim of the thin-film cell group is to develop polycrystalline silicon (poly-Si) thin-film solar cells on glass, an approach that is widely recognised as being a pathway towards substan-tially lowering the cost of photovoltaic solar elec-tricity.

In 2000, our main areas of work have been:

• The optimisation and charac-terisation of poly-Si films on glass resulting from the crys-tallisation of amorphous silicon films at low temper-ature (< 600°C) using alumi-nium-induced crystallisation,

• experimental studies evalu-ating the potential of the ion-assisted deposition method for the fabrication of poly-Si solar cells on glass,

• the development of a surface texturing method for glass substrates and the investi-gation of the light trapping properties of amorphous silicon films deposited on such substrates,

• two- and three-dimensional computer simulations of vari-ous effects in poly-Si thin-film cells, such as recom-bination at grain boundaries,

• fundamental experimental investigations of the parallel multijunction thin-film sili-con solar cell, a device struc-ture proposed at UNSW and presently being commercial-ised by Pacific Solar Pty. Ltd. in Sydney.

Optimisation & characterisation of poly-Si films made on glass by metal-induced crystallisation of a-Si One of the most challenging problems for the development of poly-Si thin-film solar cells is the growth of crystalline silicon on foreign, low-cost and low-temperature substrates. We are investigating aluminium-induced crystallisation (AIC) as an alter-native process to the commonly used processes such as laser crystallisation and solid phase crystallisation (SPC). Using AIC, we have achieved substantially faster crystal growth than SPC and crystal grains larger than in laser crys-tallised material. In the AIC process studied in our group, adjacent aluminium and amorphous silicon (a-Si) layers exchange places when heated at a temperature well below the eutectic temperature (577°C) of the Si/Al binary system. During the exchange process, a poly-Si film is formed at the original position of the Al film. The Al/Si layered structure is fabricated on glass substrates (Corning 1737). The Al and a-Si are deposited by thermal evaporation and dc magnetron sputtering, respec-tively. The crystallisation takes

Fig. 21: FIB pictures of a glass substrate sample (a) before annealing and (b) after annealing at 500°C for 30 min.

19

place during a subsequent iso-thermal annealing process at a temperature in the range 350 -525°C. Thus, simple and indus-trially relevant deposition and processing techniques are em-ployed.

Fig. 22 Fig. 21 shows cross-sectional focussed ion beam (FIB) micro-scope pictures of the samples before (a) and after (b) annealing at 500°C. It can be seen that the annealing produces a fully crys-tallised, continuous Si film co-vered by a layer of Al with Si in-clusions. Obviously, for subse-quent processing, the Al+(Si) layer visible in Fig. 21(b) must be removed. In our baseline process, we use a simple Al etch

for this purpose. However, since this only eliminates the Al, a rather rough surface with Si islands remains, as shown in Fig. 22.

In order to determine whether or not the poly-Si films made by AIC are of a sufficient quality for use as absorber material in poly-Si thin-film solar cells, we fabri-cated test cells as shown in Fig. 23. The microcrystalline n-type emitter and the TCO front contact layer were both depo-sited by researchers at the Uni-versity of Neuchatel, Switzer-land.

Fig. 23 Spectral response measurements taken on these samples (see lower plot in Fig. 23) showed that the minority carrier diffusion length in the p-type poly-Si films made by AIC is only about 0.1 µm. This value is far too low to enable the use of these AIC films as absorber layers in thin-film solar cells. However, as will be shown below, the AIC films are excellent seeding layers on glass, enabling the epitaxial thickening at low temperature by a suitable Si deposition method. As can be seen in Fig. 22, the surface of the AIC-grown Si film is very rough. This may constitute a problem for certain applications. We have developed a process that addresses this problem. As can be seen in Fig. 24, a smooth surface is created by our novel process.

Fig. 24

Fig. 22: Cross-sectional FIB picture of an annealed glass substrate sample after Al etching.

Glass

p+ pc-Si (AIC),~0.5 µm

n++ µc-Si (~20 nm)

TCO (70 nm)

Contact

Contact

300 400 500 600 700 800 900 10000

5

10

15

20

25

Measurement

Simulation Ln = 103 nm

Simulation Ln = 90 and 120 nm

Reflectance

EQ

E, R

efle

ctan

ce [%

]

Wavelength [nm] Fig. 23: (Top) Structure of the poly-Si thin-film solar cells made on glass sub-strates. (Bottom) Measured external quantum efficiency of such a cell under front illumination. The three solid lines are fits obtained with the computer simu-lation program PC1D. The dashed line is the reflectance determined by PC1D.

Surface

Poly-Si

Glass

Fig. 24: Focussed ion beam micrograph of the 0.5 µm thick poly-Si seeding layer prepared on glass by Al-induced crystallisation of a-Si.

20

Thin-film silicon solar cells on glass by ion-assisted deposition The major aim of the thin-film approach to solar cells is cost reduction while maintaining good efficiency. It is therefore crucial to develop processes that are compatible with cheap substrate materials (e.g. standard glass). The use of standard glass restricts cell processing to rela-tively low temperatures below about 600°C. For most thin-film technologies, this restriction leads to comparatively low material quality, a drawback that can only be compensated for using specialised cell structures such as the parallel multi-junction cell. In contrast to the latter approach (which is foll-owed by Pacific Solar Pty. Ltd.), the thin-film group at UNSW aims at developing a process for high-quality polycrystalline sili-con films on glass at low tem-perature (< 600°C). One of the silicon growth/ deposition methods that we are investigating is “ion-assisted deposition” (IAD). Using ele-vated temperatures in the 600 -800°C range and silicon wafers as substrate, the company ANTEC in Germany has already proven that IAD is capable of providing highest-quality crys-talline silicon films. In 2000 we continued our cooperation with ANTEC, enabling us to perform first experimental studies using ANTEC equipment in Germany. In parallel, development and construction work on our own

IAD system at UNSW continued throughout 2000 and now has come to its final stage. Fig. 25 shows the main features of an IAD system. After the silicon atoms are ionised, they can be accelerated towards the substrate using an electric field. This additional energy enables the deposited silicon atoms to take over the crystalline order of the substrate even at low tem-peratures.

Fig. 25: Schematic of an ion-assis-ted deposition (IAD) system for the fabrication of good-quality poly-Si films at low temperature (< 600°C).

When using glass as substrate, it has to be coated by a layer of crystalline silicon that consists of large-area grains with good crys-tallographic structure. Such a “seeding layer” has been devel-oped by our group using alumi-nium-induced crystallisation of amorphous silicon (see above).

The ion-assisted growth then takes over the crystal structure and grain size of the seeding layer, allowing the fabrication of large-grained, high-quality poly-crystalline silicon films on glass at low temperature.

Fig. 26 As a major milestone, in 2000 we have been able to experi-mentally realise high-quality poly-Si films on seeded glass by means of IAD at a comparatively low temperature of 630°C. Fig. 26 shows a transmission electron microscope (TEM) pic-ture of one of the fabricated samples. Thin-film silicon solar cells on glass by hot-wire CVD The result of Fig. 26 clearly shows that the poly-Si seeding layers developed at UNSW are the key to the achievement of ‘thick’, large-grained poly-Si films on glass at low temper-ature. However, with regard to industrial application, the ion-assisted deposition method has the drawback of requiring high-vacuum conditions (pressure < 10-6 mbar). It would be ideal if a simpler Si deposition method could be found that can achieve the same results as the ion-assisted deposition method (see Fig. 26) but at lower cost. An interesting candidate for this purpose is hot-wire chemical vapor deposition (HWCVD). This is a rather new deposition method for poly-Si that has a

~ 5

µm

Glass

Poly-Si by IAD

Seeding layer by AIC

Fig. 26: Transmission electron microscope picture of a large-grained poly-crystalline silicon film fabricated by IAD at 630°C on a glass substrate covered by a poly-Si seeding layer.

21

number of important properties:

• It is a low-temperature meth-od (and hence is compatible with glass substrates).

• It does not require a plasma (in contrast to PECVD, the standard method used in the industry) and hence is a very simple method.

• It has a high deposition rate (> 2 nm/s), which is 10 times larger than that of PECVD.

• It is easily upscaleable to very large areas.

• It gives device-quality poly-Si.

Given these exciting properties of the HWCVD method, we are presently establishing such a sys-tem within our Centre. Fig. 27 shows a schematic of a HWCVD machine.

Fig. 27 Fig. 28

Texturing of glass substrates Fig. 29

Our glass texturing work has advanced such that borosilicate glass is now routinely embossed at 720°C using two types of singlecrystal silicon die textures: (a) inverted, regularly spaced pyramids 10 µm across, and (b) randomly sized, upright pyra-mids ranging 2 - 10 µm across. Good uniformity of the em-bossed texture is achieved using a gimbal and limiting tubes to

balance the amount of thinning of the glass at each corner. The tubes provide a reaction force needed to rotate the gimbal where necessary when 100 kg/cm2 is applied at the em-bossing temperature; the rotation is made possible by glass flow. Fig. 28 shows our embossing apparatus. The silicon dies with an area of 5.0 cm × 2.2 cm are strengthened by cutting them with a laser at 45° to the <110> crystal orientation. A coating of TixAl1-xN, with x ≈ 0.5, is sputter-ed onto the die surface to

prevent the glass bonding. The antireflection and light trapping benefit of an inverted-pyramid texture embossed on the glass substrate is shown in Fig. 29. For these measurements, the glass was coated with a 5.5 µm thick a-Si:H film. Scanning elec-tron micrographs of the a-Si:H film on the pyramidally textured glass are shown in Fig. 30.

Fig. 30 Scaling up the embossed area to 100 cm2 and beyond will ne-cessitate a Si die thickness of over 3 mm to withstand the higher force required to separate the embossed glass. This rules

Process gases(silane & hydrogen)

Gas flow controller

Vacuumpumps

Hot wire(tungsten)

Glasssubstrate

Substrate holder(heatable)

Poly-Si film

Vacuumchamber

Power supplyhot wires

Power supplysubstrate holder

Exhaust

Fig. 27: Schematic of the hot-wire chemical vapor deposition system for silicon being built at UNSW.

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ctan

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abso

rban

ce

Fig. 29: Measurements showing the effect of substrate texturing for a 5.5 µm thick a-Si:H film deposited onto an untextured (squares), a sandblasted (diamonds) and an embossed (pyramids, circles) glass substrate. The absorbance is based on reflec-tance and transmission measurements. The light is incident from the glass side and no reflector is used on the a-Si:H side. Left graph: Extrapolated lines show estimated front reflectance for weakly absorbed wavelengths. Right graph: Absorbance (frac-tion internally absorbed; unity at 650 nm) & absorbance enhancement (bell-shaped curves). Also included in the right graph (lines) are, for comparison, estimated curves for randomly scattered light.

Fig. 28: Glass embossing ass-embly, which is inserted into a vertical furnace. Pressure is applied hydraulically via rods above (shown) and below the ass-embly.

22

out the use of inverted pyramids, as the photolithographic ex-posure step used to produce this texture requires a silicon wafer thickness under 0.5 mm to en-sure its surface conforms with the mask under vacuum. We are presently investigating the random-pyramid texture as a candidate for scaling up since this texture can be produced without photolithography. Preli-minary results from this approach are shown in Fig. 31.

Fig. 31: SEM image of a glass sur-face with random pyramids.

Simulation of multijunction solar cells The parallel multijunction (PMJ) thin-film solar cell has the potential to increase the effi-ciency on low-cost, poor-quality polycrystalline silicon. Com-mercialisation of this technology is currently under way at Pacific Solar in Sydney. Here at UNSW, one research strand is focusing on a more fundamental study of this device structure.

Fig. 32 We applied two-dimensional (2D) numerical simulations to

reproduce the measured current-voltage (I-V) curves of fabricated devices. To do so, we initially simulated a series of standard PERL cells that were exposed to various doses of 10-MeV protons to controllably degrade the sili-con quality. We were able to reproduce the I-V curves of these cells using the Shockley-Read-Hall formalism with a single defect energy level of Ec -0.42 eV, in agreement with results from IMEC, Belgium. As a next step, we applied this model to PMJ cells that also obtained various proton doses. Since the density of defects created in silicon by 10-MeV protons depends on the silicon doping level, we extended the simulation model by such a doping dependence, as found in the literature. We were able to reproduce the measured I-V

curves of PMJ cells very precise-ly up to irradiation doses of 3×1014 protons/cm2 (see Fig. 32). These simulations give us impor-tant and quantitative insight into the local recombination losses in both the quasi-neutral and the p-n junction depletion regions. Recombination in p-n junction depletion regions An increasing number of cell designs have interdigitated p- and n-type regions. At the margin of these regions, the p-n junction borders the surface, causing additional recombina-tion losses. These mechanisms are rather intricate since the electrostatic conditions in these device regions are governed by both the p-n junction depletion region and the depletion/inver-sion layer of the surface. We investigated such recom-bination mechanisms by means of 2D modelling. We derived a numerical model based on fabricated devices that contain no other unknown loss mechan-ism, such as high-efficiency PERL cells or proton-irradiated cells. We found that the ideality factors of the I-V curves of such cells increase at low voltages in a distinctly different manner compared to shunt leakage currents. We also showed that a

Fig. 30: Left: Scanning electron micrograph (SEM) of borosilicate glass embossed with 10 µm × 10 µm pyramids. Foreground view uncoated, rear coated with a 5.5 µm thick a-Si:H film. Right: SEM of the film in profile (film is grey, glass is black) viewed at 45° above the substrate plane, obtained by focussed ion beam milling of a small portion of the coated surface.

0 0.2 0.4 0.6 0.810

-6

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102

ExperimentSimulations

Voltage [ V ]

Cur

rent

den

sity

[ m

A/c

m

]

Parallel multijunction cells in the dark at 300 K

Increasing irradiation dose2

Fig. 32: Measured (symbols) and simulated (lines) I-V curves of parallel multijunction (PMJ) silicon solar cells.

23

degraded oxide quality, near where the p-n junction borders on the surface, is mainly respon-sible for the observed losses in fill factor and open-circuit vol-tage of our test cells. As the establishment of the model was based on various experimental devices, it is appli-cable to many other types of cell design having various material quality and geometrical struc-tures. Simulations of grain boundaries The behaviour of poly- and multicrystalline devices is rather complex to model. On the one hand, the amount of trapped charge at the grain boundaries depends on the position of the quasi-Fermi levels, causing complicated electrostatic con-ditions. On the other hand, the intragrain properties, e.g. the lifetime of excess minority carriers within the grains, do not solely depend on the material quality within the grains, but are strongly influenced by the grain boundaries as well. To reduce this complexity, most models 'lump', for example, the influ-ence of various recombination mechanisms into a single effec-tive diffusion length (or into an effective recombination velocity at the boundary, etc). We aim to model polycrystalline devices on the basis of the underlying physical effects rather than by means of 'lumped' input parameters. To do so, it is crucial to simulate in three dimensions. Hence, we have started to numerically model polycrystalline silicon cells in three dimensions. The investigated grain size is in the range 1 µm to 1000 µm. Pre-vious three-dimensional (3D) calculations found in the liter-ature were done using analytical models, while we are solving the fully coupled set of semicon-ductor differential equations. Nowadays, computers with

1 GB RAM and 1 GHz fre-quency are affordable and make such 3D numerical calculations feasible. We found that 3D effects are very important, especially for grain sizes below 1 mm. This is so because in 3D the flow of many photo-generated carriers is determined by two adjacent boundaries, while in two dimen-sions all boundaries are parallel such that the carriers can only flow towards a single boundary. Comparing our simulations with a wide range of published experiments indicates that the recombination velocity at the grain boundaries, for grain sizes between 1 and 100 µm, lies in the range 105 - 106 cm/s, regard-less of the deposition method and the grain size. Quantum wires in silicon In addition to the thin-film solar cell work described above, we are also investigating new meth-ods of fabricating quantum wires in silicon. Such wires are a key feature of upcoming nanoscale semiconductor devices. As yet, such wires have only been rea-lised using sophisticated app-roaches and, in general, expen-sive III-V semiconductor mater-

ials. In contrast, in this project we aim at fabricating quantum wires in today's standard mater-ial, silicon, using a strikingly simple approach that is com-patible with the mainstream microelectronics industry. The basic idea of the approach is the one-dimensional localisation of electrical charges within an insulator on a silicon wafer by means of an atomic-resolution microscope. By creating a suffi-ciently large charge density, a quantum wire can possibly be induced in the silicon. As insul-ator we use a double-layer stack consisting of an ultra-thin (~1.5 nm) thermal oxide and a plasma silicon nitride film.

Fig. 33 As a first experiment for realising the above novel method of fabricating quantum wires in silicon, we investigated the hysteresis effect in capacitance-voltage measurements caused by the charged defects (so-called “K Centres”) in the insulator stack. As Fig. 33 shows, these K Centres can controllably be charged or discharged. This result indicates that the double insulator stack is well suited for the one-dimensional localisation of electrical charges by means of an atomic-resolution micros-cope.

Fig. 34

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acita

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[pF

]

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after recharging of insulator charges

Fig. 33: Measured capacitance-voltage curve (300 K) of a large-area Al/SiN/SiO/p-Si capacitor in the as-fabricated state (left curve), after application of a large negative gate voltage at 300 K for 19 hrs (right curve), and after additional application of a large positive voltage for 20 min at 200°C (middle curve).

24

In 2000, we applied an atomic-force microscope (AFM) to MOSFET-type samples to neu-tralise, by means of an electric field, the charged K Centres along a 9 µm long line. As shown in Fig. 34, a non-conduc-ting “wire” with a width of about 150 nm has been realised as yet. Through refinements of the method, we expect to be able to achieve conducting wires with widths below 100 nm.

µµm

800

400

nm

Fig. 34: AFM picture of the MOSFET-type sample after the neutralisation of insulator charges along a 9 µm long line with an AFM. The resulting ‘charge line’ within the SiO/SiN insulator is about 150 nm wide.

25

The Centre’s external contacts to local and international research institutes and companies work-ing in the photovoltaic sector were wide and varied, with staff visits in several cases. Visitors to the Centre for ex-tended periods of time included researchers from China, Ger-many, Italy and Switzerland. In addition to students from UNSW and other Australian uni-versities, the Centre attracted postgraduate students from Ger-many, Pakistan, South Korea, Spain, Sweden, Taiwan, and Thailand. The major external contacts in 2000 included the following: Research institutions:

• Australian National University (ANU), Canberra, Australia

• Bavarian Centre for Applied Energy Research (ZAE Bay-ern), Erlangen, Germany

• CSIRO Telecommunications and Industrial Physics, Mars-field, Australia

• Dalian Railway Institute, Dalian, China

• ECN Netherlands Energy Research Foundation, Petten, Netherlands

• Fraunhofer Institute for Solar Energy Systems (FhG-ISE), Freiburg, Germany

• Georgia Institute of Techno-logy, Atlanta, USA

• Hahn Meitner Institute Berlin, Berlin, Germany

• Hebei University, Baoding, China

• IMEC, Leuven, Belgium

• Institute for Solar Energy Research Hameln/Emmerthal (ISFH), Emmerthal, Germany

• Korea Advanced Institute of Science and Technology (KAIST), Taejon, South Korea

• Murdoch University, Perth, Australia

• National Renewable Energy Laboratory (NREL), Golden, USA

• Polytechnical University of Madrid, Madrid, Spain

• Research Centre Jülich, Jülich, Germany.

• Sandia National Laboratories, Albuquerque, USA

• Seoul National University of Technology (SNUT), Seoul, South Korea

• Swiss Federal Institute of Technology (ETH Zurich), Zurich, Switzerland

• University of Canterbury,

Christchurch, New Zealand

• University of Konstanz, Konstanz, Germany

• University of Neuchatel, Neuchatel, Switzerland

• University of Stuttgart, Stutt-gart, Germany

Companies:

• Antec GmbH, Kelkheim, Germany

• BP Solar, Surrey, UK

• Crystal Systems, Salem, USA

• ENEA Research Centre, Portici, Italy

• Eurosolare, Nettuno, Italy

• Micro Materials & Research Cons. Pty. Ltd. (MMRC), Melbourne

• Pacific Solar, Botany, Aus-tralia

• Samsung SDI, Suwon, South Korea

• Shin-Etsu Handotai Corp., Isobe, Japan

• Sinton Consulting, Boulder, USA

• SunPower, Sunnyvale, USA

• Topsil Semiconductor Materials, Denmark

EXTERNAL CONTACTS

26

2000 was the Photovoltaics Special Research Centre’s first year of a new era of operation without direct Special Research Centre funding from the Austral-ian Research Council (ARC). Total income at A$ 1 075 500 was significantly less than previous Centre income levels, for example, A$ 3.6 M in 1998 and A$ 1.7M in 1999. This reduction in income has necessi-tated a rationalisation of activities within the Centre.

Fig. 35 The immediate financial challenge ahead is to find ways to support the sophisticated laboratory and facility infrastruc-ture provided to the Centre over nine years ago and substantially enhanced during the subsequent period of ARC Special Research Centre funding. The Centre’s semiconductor pro-cessing infrastructure, coupled with its excellent research record, has long been a key fac-tor in attracting the best local and overseas researchers to the

group. Investment in high-quality infrastructure and a stable workforce of experienced engineering and technical support is imperative for con-tinued leading edge experi-mental research. To successfully continue to support and maintain these valuable resources requires con-tinual improvements to oper-ating efficiency. However, the highest financial priorities of the future are to attract additional income from other sources such that the required research infra-structure can be maintained in a useable state. Income to the Centre in 2000 fell into the following categories:

• Small and Large ARC Grants (“Other ARC Grants”)

• Royalty and Rental income (“Other Income Sources/ Royalties and Rent”)

• UNSW + Research Quan-tum (“Host Institution Support”).

The splits are shown in Fig. 35. It is emphasised that several of these income sources (rental income, research quantum, royalties) are a direct result of the successful work of the Centre conducted during the 9-year ARC Special Research Centre funding period (1991-1999).

FINANCIALS

Other ARC Grants51%

Host Institution Support23%

Other Income Sources/Royalties +

Rent26%

Fig. 35: Income of the Photovoltaics Special Research Centre in the calendar year 2000.

27

PATENTS, PATENT APPLICATIONS P. Widenborg and A.G. Aberle, “Method of preparation for poly-crystalline semiconductor films”, Australian Provisional Patent Application, Dec. 2000. BOOKS, BOOK CHAPTERS M.A. Green, “Power to the Peo-ple” (UNSW Press, Sydney, 2000). REFEREED JOURNALS A.G. Aberle, “Surface passiva-tion of crystalline silicon solar cells - A review”, Progress in Photovoltaics 8, 473-487 (2000). A.G. Aberle, “Overview on SiN surface passivation of crystalline silicon solar cells”, Solar Energy Materials and Solar Cells 65, 239-248 (2001). P.P. Altermatt, R.A. Sinton, G. Heiser, “Improvements in nume-rical modelling of highly injec-ted crystalline silicon solar cells”, Solar Energy Materials and Solar Cells 65, 149-155 (2001). R. Corkish, P.P. Altermatt, G. Heiser, “Numerical simulation of electron beam induced current near a silicon grain boundary and impact of a p-n junction space charge region, Solar Energy Materials and Solar Cells 65, 63-69 (2001). M.A. Green, The future of crys-talline silicon solar cells, Pro-gress in Photovoltaics 8, 127-139 (2000). M.A. Green, K. Emery, D. King, S. Igar, and W. Warta, “Solar cell efficiency tables (Version

15)”, Progress in Photovoltaics 8, 187-195 (2000). M.A. Green, K. Emery, D. King, S. Igar, and W. Warta, “Solar cell efficiency tables (Version 16)”, Progress in Photovoltaics 8, 377-383 (2000). M.A. Green, “Photovoltaics: Technology overview”, Energy Policy 28, 989-998 (2000). M.A. Green, “Silicon solar cells: At the crossroads”, Progress in Photovoltaics 8, 443-450 (2000). M.A. Green, J. Zhao, A. Wang and S.R. Wenham, “Progress and outlook for high-efficiency crystalline silicon solar cells”, Solar Energy Materials and Solar Cells, 65, 9-16 (2001). B. Kuhlmann, A.G. Aberle, R. Hezel, and G. Heiser, “Simu-lation and optimization of metal-insulator-semiconductor inver-sion-layer silicon solar cells”, IEEE Transactions on Electron Devices 47, 2167-2178 (2000). K.R. McIntosh, G. Boonprakai-kaew, and C.B. Honsberg, “An experimental technique to meas-ure the shunt resistance across a local region of a floating junc-tion”, Solar Energy Materials and Solar Cells 64, 353-361 (2000). O. Nast, S. Brehme, S. Pritchard, T. Puzzer, A.G. Aberle, and S.R. Wenham, “Aluminium induced crystallisation of silicon on glass for thin-film solar cells", Solar Energy Materials and Solar Cells 65, 385-392 (2001). D.H. Neuhaus, P.P. Altermatt, R.P. Starrett, and A.G. Aberle, “Determination of the density of states in heavily doped regions of silicon solar cells”, Solar Energy Materials and Solar Cells 65, 105-110 (2001).

A. Rohatgi, P. Doshi, J. Mosch-ner, T. Lauinger, A.G. Aberle, D.S. Ruby, “Comprehensive study of rapid, low-cost silicon surface passivation technolo-gies”, IEEE Transactions Electron Devices 47, 987-993 (2000). J. Schmidt, M. Kerr, and P.P. Altermatt, “Coulomb-enhanced Auger recombination in crystal-line silicon at intermediate and high-injection densities”, Journal of Applied Physics 88, 1494-1497 (2000). J.O. Schumacher, P.P. Altermatt, G. Heiser, and A.G. Aberle, “Application of an improved band-gap narrowing model to the numerical simulation of re-combination properties of phos-phorus-doped silicon emitters”, Solar Energy Materials and Solar Cells 65, 95-103 (2001). S.R. Wenham, J. Zhao, X. Dai, A. Wang and M.A. Green, “Surface passivation in high effi-ciency silicon solar cells”, Solar Energy Materials and Solar Cells 65, 377-384 (2001). J. Zhao, A. Wang, P.P. Altermatt and G. Zhang, “Peripheral loss reduction of high efficiency silicon solar cells by MOS gate passivation, by poly-Si filled grooves and by cell pattern design”, Progress in Photo-voltaics 8, 201-210 (2000). J. Zhao, A. Wang and M.A. Green, “Performance degra-dation in CZ(B) cells and im-proved stability high efficiency PERT and PERL silicon cells on a variety of SEH MCZ(B), FZ(B) and CZ(Ga) substrates”, Progress in Photovoltaics 8, 549-558 (2000). J. Zhao, A. Wang and M.A. Green, “High-efficiency PERL and PERT silicon solar cells on

PUBLICATIONS

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FZ and MCZ substrates”, Solar Energy Materials and Solar Cells 65, 429-435 (2001). J. Zhao, A. Wang and M.A. Green, “24.5% efficiency PERT silicon solar cells on SEH MCZ substrates and cell performance on other SEH CZ and FZ sub-strates”, Solar Energy Materials and Solar Cells 66, 27-36 (2001). CONFERENCE PAPERS P.P. Altermatt, J. Schmidt, M. Kerr, G. Heiser, and A.G. Aber-le, “Exciton-enhanced Auger recombination in crystalline sili-con under intermediate and high injection conditions”, Conf. Re-cord, 16th European Photo-voltaic Solar Energy Conference, Glasgow, May 2000 (in press). P.P. Altermatt, J.O. Schumacher, A. Cuevas, S.W. Glunz, R.R. King, G. Heiser, A. Schenk, “The extraction of the surface recom-bination velocity of Si:P emitters using advanced silicon models”, Conf. Record, 16th European Photovoltaic Solar Energy Con-ference and Exhibition, Glas-gow, UK, May 2000 (in press). O. Breitenstein, M. Langen-kamp, and K.R. McIntosh, “Localisation of shunts across the floating junction of DSBC solar cells by lock-in thermo-graphy”, Conf. Record, 28th IEEE Photovoltaic Specialists Confer-ence, Anchorage, USA, Sep. 2000 (in press). S.P. Bremner, R. Corkish, and C.B. Honsberg, “Impact of non-ideal recombination and trans-port mechanisms in multiple band gap solar cells”, Conf. Record, 28th IEEE Photovoltaic Specialists Conference, Anchor-age, USA, Sep. 2000 (in press). S.P. Bremner and C.B. Hons-berg, “LO phonon assisted capture and escape for a quan-tum well”, Proc. 16th European Photovoltaic Solar Energy Con-

ference and Exhibition, Glas-gow, UK, May 2000 (in press). P. Campbell and M. Keevers, “Light trapping and reflection control for silicon thin films deposited on glass substrates textured by embossing”, Conf. Record, 28th IEEE Photovoltaic Specialists Conference, Anchor-age, USA, Sep. 2000 (in press). R. Corkish, K.L. Luke, P.P. Alter-matt, and G. Heiser, “Simula-ting electron-beam-induced current profiles across p-n junctions”, Proc. 16th European Photovoltaic Solar Energy Con-ference and Exhibition, Glas-gow, UK, May 2000 (in press). R. Corkish, R. Lowe, R. Largent, C.B. Honsberg, N. Shaw, R. Constable, and P. Dagger, “Montague Island photovoltaic/ diesel hybrid system”, Conf. Record, 16th European Photo-voltaic Solar Energy Conference and Exhibition, Glasgow, UK, May 2000 (in press). R. Corkish, P. Dagger, R. Largent, C. Honsberg, and R. Constable, “Montague Island photovoltaic/diesel hybrid sys-tem”, Proc. Solar 2000, Aus-tralian and New Zealand Solar Energy Society, Brisbane, Nov./ Dec. 2000 (in press). J.E. Cotter, N.C. Shaw, and M.F. Hossain, “Novel processes for simplified buried contact solar cells”, Conf. Record, 28th IEEE Photovoltaic Specialists Confer-ence, Anchorage, USA, Sep. 2000 (in press). J.E. Cotter, H.R. Mehrvarz, K.R. McIntosh, C.B. Honsberg, and S.R. Wenham, “Combined emitter and groove diffusion in buried contact solar cells”, Conf. Record, 16th European Photo-voltaic Solar Energy Conference and Exhibition, Glasgow, UK, May 2000 (in press). J.E. Cotter, P. Campbell, and N.C. Shaw, “Light trapping in thin silicon solar cells with

pigmented diffuse reflectors and textured rear surfaces, Conf. Record, 16th European Photo-voltaic Solar Energy Conference and Exhibition, Glasgow, UK, May 2000 (in press). M.A. Green, “Recent improve-ments in silicon solar cell per-formance and paths to commer-cialization”, Proc. 16th Euro-pean Photovoltaic Solar Energy Conf. and Exhibition, Glasgow, UK, May 2000 (in press). M.A. Green, “Status of crys-talline photovoltaic technology”, Conf. Record, World Renewable Energy Congress VI (in press). N.-P. Harder, J.A. Xia, S. Oel-ting, O. Nast, P. Widenborg, and A.G. Aberle, “Low-temperature epitaxial thickening of sub-micron poly-Si seeding layers on glass made by aluminium-induced crystallisation”, Conf. Record, 28th IEEE Photovoltaic Specialists Conference, Anchor-age, USA, Sep. 2000 (in press). C.B. Honsberg, A. Slade, K.R. McIntosh, B. Vogl, J.E. Cotter, and S.R. Wenham, “Comparison of rear surface passivation tech-niques for buried contact solar cells”, Proc. 16th European Pho-tovoltaic Solar Energy Confer-ence and Exhibition, Glasgow, UK, May 2000 (in press). C.B. Honsberg, R. Corkish, and S.P. Bremner, “Limiting efficien-cy of solar cells with multiple energy levels”, Proc. 16th Euro-pean Photovoltaic Solar Energy Conf. and Exhibition, Glasgow, UK, May 2000 (in press). M. Keevers and P.P. Altermatt, “Experimental investigation of the impact of junction space-charge region recombination in heavily defected parallel multi-junction thin film silicon solar cells, Proc. 16th European Pho-tovoltaic Solar Energy Confer-ence and Exhibition, Glasgow, UK, May 2000 (in press).

29

K.R. McIntosh, P.P. Altermatt, and G. Heiser, “Depletion-region recombination in silicon solar cells: When does mDR=2?”, Proc. 16th European Photo-voltaic Solar Energy Conference and Exhibition, Glasgow, UK, May 2000 (in press). K.R. McIntosh and C.B. Hons-berg, “The influence of edge recombination on a solar cell's I-V curve”, Proc. 16th European Photovoltaic Solar Energy Con-ference and Exhibition, Glas-gow, UK, May 2000 (in press). D.H. Neuhaus, P.P. Altermatt, R.P. Starrett, A. Schenk and A.G. Aberle, “The density of states in heavily doped regions of silicon solar cells”, Conf. Record, 28th IEEE Photovoltaic Specialists Conference, Anchorage, USA, Sep. 2000 (in press). D.H. Neuhaus, R. Bardos, L. Feitknecht, T. Puzzer, M.J. Keevers, and A.G. Aberle, “Min-ority carrier properties of single- and polycrystalline silicon films formed by aluminium-induced crystallisation”, Proc. 28th IEEE Photovoltaic Specialists Confer-ence, Anchorage, USA, Sep. 2000 (in press). A. Parretta, P. Grillo, A. Sarno, P. Maddalena, P. Tortora, J. Zhao and A. Wang, "Light trapp-ing properties of c-Si solar cells studied by reflectance and current measurements at vari-able angles of the incident light", Conf. Record, 16th European Photovoltaic Solar Energy Con-ference and Exhibition, Glas-gow, UK, May 2000 (in press). S.C. Pritchard, S.R. Wenham and C.B. Honsberg, “Junction voltages and carrier flow in thyristor-structure solar cells”, Conf. Record, 16th European Photovoltaic Solar Energy Con-ference and Exhibition, Glas-gow, UK, May 2000 (in press). B. Richards, J.E. Cotter, C.B. Honsberg, F. Ferrazza, and S.R. Wenham, “Novel uses of TiO2 in

crystalline silicon solar cells”, Proc. 28th IEEE Photovoltaic Specialists Conference, Anchor-age, USA, Sep. 2000 (in press). T. Saitoh, H. Hashigami, X. Wang, T. Abe, T. Igarashi, S. Glunz, S. Rein, W. Wettling, A. Ebong, B.M. Damiani, A. Rohatgi, H. Ohtuka, T. Wara-bisako, J. Zhao, M. Green, J. Schmidt, A. Cuevas, A. Metz and R. Hezel, “Suppression of light-induced degradation of minority-carrier lifetime in low-resistivity CZ silicon wafers and solar cells”, Proc. 16th European Photovoltaic Solar Energy Con-ference and Exhibition, Glas-gow, UK, May 2000 (in press). N.C. Shaw, J.E. Cotter, and P.R. Campbell, “Internal optical pro-perties of pigmented diffuse reflectors for thin silicon cells”, Conf. Record, 16th European Photovoltaic Solar Energy Con-ference and Exhibition, Glas-gow, UK, May 2000 (in press). N.C. Shaw and S.R. Wenham, “Design of a novel static con-centrator lens utilising total internal reflection surfaces”, Conf. Record, 16th European Photovoltaic Solar Energy Con-ference and Exhibition, Glas-gow, UK, May 2000 (in press). A.M. Slade, C.B. Honsberg, and S.R. Wenham, “Passivated boron emitters for n-type bifacial buried contact solar cells”, Conf. Record, 28th IEEE Photovoltaic Specialists Conference, Anchor-age, USA, Sep. 2000 (in press). A.M. Slade, K.R. McIntosh, C.B. Honsberg, and S.R. Wenham, “Optimisation of the processing sequence for bifacial buried contact solar cells”, Proc. 28th IEEE Photovoltaic Specialists Conference, Anchorage, USA, Sep. 2000 (in press). A.M. Slade, C.B. Honsberg, and S.R. Wenham, “Processing and characterisation of boron diffused back surface fields in mono- and bifacial buried

contact solar cells”, Conf. Record, 16th European Photo-voltaic Solar Energy Conference and Exhibition, Glasgow, UK, May 2000 (in press). B. Vogl, A.M. Slade, C.B. Hons-berg, J.E. Cotter, and S.R. Wen-ham, “Inclusion of dielectric films for rear surface passivation of buried contact solar cells”, Proc. 28th IEEE Photovoltaic Specialists Conference, Anchor-age, USA, Sep. 2000 (in press). J.E. Wu and A.G. Aberle, “Charge-induced quantum wires in silicon”, Technical Digest, 44th International Conference on Electron, Ion, and Photon Beam Technology & Nanofabri-cation (EIPBN 2000), Palm Springs, USA, 338-339 (2000). J.E. Wu, E. Gauja, B. Vogl, T. Puzzer, N.E. Lumpkin, A.S. Dzurak, R.G. Clark, and A.G. Aberle, “Application of charged insulator defects for the reali-sation of low-dimensional struc-tures in silicon”, Book of Ab-stracts, 11th International Semi-conducting and Insulating Materials Conference (SIMC-XI 2000), Canberra, July 2000. J. Zhao, A. Wang, M.A. Green, “High efficiency PERT cells on a variety of single crystalline sili-con substrates”, Conf. Record, 16th European Photovoltaic Solar Energy Conference and Exhibition, Glasgow, UK, May 2000 (in press). J. Zhao, A. Wang and M.A. Green, “High efficiency PERT cells on SEH CZ(Ga) and related silicon substrates”, Workshop II on Light Degradation of Carrier Lifetimes in CZ-Si Solar Cells -International Joint Research. 16th European Photovoltaic Solar Energy Conference and Exhibition, Glasgow, UK, May 2000 (in press). J. Zhao, A. Wang, M. Keevers and M.A. Green, “High effi-ciency PERT cells on SEH p-type Si substrates and PERT cells on

30

SEH n-type Si substrates”, Conf. Record, Solar’2000 Conference, Brisbane, AUS, 474-482 (2000). THESES a) Doctoral Linda Koschier, “Multijunction and novel Si photovoltaic device structures”, School of Electrical Engineering and Telecommuni-cations, UNSW, April 2000. b) Masters F. Hossain, “ Rear contact grid formed by laser alloying alu-minium and silicon”, MEngSc thesis, School of Electrical Engineering and Telecommuni-cations, UNSW, August 2000. A. Ueranantasun, “Evaluation of simple measurement technique for sheet resistivity in inversion layer with TiO2 and Cs”, MEngSc

thesis, School of Electrical Engineering and Telecommuni-cations, UNSW, March 2000. c) Undergraduate K. Anwar, “Investigation of alu-minium back surface fields for buried contact solar cells", Final-year thesis project, School of Electrical Engineering and Tele-communications, UNSW, Nov. 2000. P. Cousins, “Single high temper-ature step selective emitter buried contact solar cell”, Final-year thesis project, School of Electrical Engineering and Tele-communications, UNSW, Nov. 2000. M.F. Huang, “Emitter recom-bination in silicon p-n junction diodes”, Final-year thesis pro-ject, School of Electrical Engin-eering and Telecommunications, UNSW, Nov. 2000.

T.H. Oh, “Fabrication and cha-racterisation of silicon nitride films for photovoltaic appli-cations”, Final-year thesis pro-ject, School of Electrical Engin-eering and Telecommunications, UNSW, June 2000. G. Preema, “Analysis of an ion-assisted deposition system for silicon by numerical simula-tion”, Final-year thesis project, School of Electrical Engineering & Telecommunications, UNSW, Nov. 2000. C.B. Tan, “Fabrication and cha-racterization of silicon nitride/ silicon oxide/silicon inversion-layer emitters”, Final-year thesis project, School of Electrical Engineering and Telecommuni-cations, UNSW, June 2000.

OMISSIONS AND ERRATA Dr. Mark Keevers was a member of the buried-contact solar cell group during 1992-1995. In the Centre’s End-of-Grant Report, included in the Centre’s 1999 Annual Report, his name was unfortunately forgotten in the list of contributors to the buried-contact solar cell group.

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Impurity Photovoltaic CellsEun-Chel Cho

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