major research project - st. andrews...

1

Final Report of the work done, Utilization certificate&

Statement of Expenditure

ofMAJOR RESEARCH PROJECT

entitled

“Kinetics of first order phase transformation and structural studiesof Sb, Zn and Bi doped Se- In chalcogenide glasses”

UGC Reference N0.F. No. 42-780/2013 (SR), FD Diary No. 5532 dated 18-03-2014

Period of report:From 01-04-2014 to 31-03-2017

Submitted toUniversity Grants Commission

Bahadur Shah Zafar Marg, New Delhi–110002

By

Dr. Shamshad Ahmad KhanDepartment of PhysicsSt. Andrew’s College

Gorakhpur-273001, U. P., India

2

Annexure – III

UNIVERSITY GRANTS COMMISSION

BAHADUR SHAH ZAFAR MARG

NEW DELHI – 110 002

STATEMENT OF EXPENDITURE IN RESPECT OF MAJOR RESEARCH PROJECT

1. Name of Principal Investigator: Dr. Shamshad Ahmad Khan

2. Department of Principal Investigator: Department of Physics

University/College: St. Andrew’s College, Gorakhpur, U.P. India

3. UGC approval Letter No. and Date:

F. No. 42-780/2013 (SR), FD Diary No. 5532 dated 18-03-2014

4. Title of the Research Project:

“Kinetics of first order phase transformation and structural studies of Sb, Zn

and Bi doped Se –In chalcogenide glasses”.

5. Effective date of starting the project: 01-04-2014

6. (a) Period of Expenditure: From 01-04-2014 to 31-03-2017

(b) Details of Expenditure

S. No. Item AmountAllocated

Rs.

AmountReleased by

UGCRs.

ExpenditureIncurred

Rs.

Amountdue onUGCRs.

1. Books and Journals Nil Nil Nil Nil

2. Equipment 6,72,000/- 6,72,000/- 6,72,000/- Nil3. Project Fellow

Salary5,28,000/- 2,77,200/- 4,96,000/- 2,18,800/-

4. HRA of ProjectFellow

Nil Nil 99,200/- 99,200/-

5. Contingency 60,000/- 54,000/- 60,000/- 6,000/-6. Field Work (Travel

Annexure-VII)80,000/- 72,000/- 72,000/- Nil

7. Chemical andGlassware

1,00,000/- 90,000/- 1,00,000/- 10,000/-

8. Overhead 68,800/- 68,800/- 68,800/- Nil

Total 15,08,800/- 12,34,000/- 15,68,000/- 3,34,000/-

3

(c) Staff:

Date of Appointment: 01 June 2014

S.No.

Item From To AmountAllocated

Rs.

AmountReleased by

UGCRs.

ExpenditureIncurred

Rs.

Amountdue onUGCRs.

1. Project [email protected],000/-p.m. for 24months+ HRA(@ 20% of thesalary) and inthe third year@ Rs. 16,000/-p.m. for 10months+ HRA(@ 20% of thesalary)

01-06-2014 31-03-2017 5,28,000/- 2,77,200/- 5,95,200/- 3,18,000/-

The total amount allocated by UGC for the salary and HRA of project fellow Rs. 5,28,000/-The total amount paid by UGC for the salary and HRA of project fellow Rs. 2,77,200/-The total amount utilized for the salary (19 months from 01-06-2014 to 31-12-2015 @14,000/- p.m.) of project fellow

Rs. 2,66,000/-

Net balance for the salary of Project Fellow Rs. 11, 200/-The payable amount for the salary (5 months from 01-01-2016 to 31-05-2016 @14,000/- p.m. and 10 months from 01-06-2016 to 31-03-2017 @ 16,000/- p.m.) andHRA ( 34 months from 01-06-2014 to 31-03-2017 @ 20% of the salary) of projectfellow

Rs. 3,29,000/-

The amount still pending on UGC for salary + HRA of project fellow Rs. 3,18,000/-

Net amount due on UGC (Salary + HRA of project fellow + IIIrd phaseof contingency + chemical and glassware grant)

Rs. 3,34,000/-

4

Month wise salary and HRA of project fellow;

S. No. From To Salary HRA @ 20 % Total1 01-06-2014 30-06-2014 14,000/- 2800/- 16,800/-2 01-07-2014 31-07-2014 14,000/- 2800/- 16,800/-3 01-08-2014 31-08-2014 14,000/- 2800/- 16,800/-4 01-09-2014 30-09-2014 14,000/- 2800/- 16,800/-5 01-10-2014 31-10-2014 14,000/- 2800/- 16,800/-6 01-11-2014 30-11-2014 14,000/- 2800/- 16,800/-7 01-12-2014 31-12-2014 14,000/- 2800/- 16,800/-8 01-01-2015 31-01-2015 14,000/- 2800/- 16,800/-9 01-02-2015 28-02-2015 14,000/- 2800/- 16,800/-10 01-03-2015 31-03-2015 14,000/- 2800/- 16,800/-11 01-04-2015 30-04-2015 14,000/- 2800/- 16,800/-12 01-05-2015 31-05-2015 14,000/- 2800/- 16,800/-13 01-06-2015 30-06-2015 14,000/- 2800/- 16,800/-14 01-07-2015 31-07-2015 14,000/- 2800/- 16,800/-15 01-08-2015 31-08-2015 14,000/- 2800/- 16,800/-16 01-09-2015 30-09-2015 14,000/- 2800/- 16,800/-17 01-10-2015 31-10-2015 14,000/- 2800/- 16,800/-18 01-11-2015 30-11-2015 14,000/- 2800/- 16,800/-19 01-12-2015 31-12-2015 14,000/- 2800/- 16,800/-20 01-01-2016 31-01-2016 14,000/- 2800/- 16,800/-21 01-02-2016 29-02-2016 14,000/- 2800/- 16,800/-22 01-03-2016 31-03-2016 14,000/- 2800/- 16,800/-23 01-04-2016 30-04-2016 14,000/- 2800/- 16,800/-24 01-05-2016 31-05-2016 14,000/- 2800/- 16,800/-25 01-06-2016 30-06-2016 16,000/- 3200/- 19,200/-26 01-07-2016 31-07-2016 16,000/- 3200/- 19,200/-27 01-08-2016 31-08-2016 16,000/- 3200/- 19,200/-28 01-09-2016 30-09-2016 16,000/- 3200/- 19,200/-29 01-10-2016 31-10-2016 16,000/- 3200/- 19,200/-30 01-11-2016 30-11-2016 16,000/- 3200/- 19,200/-31 01-12-2016 31-12-2016 16,000/- 3200/- 19,200/-32 01-01-2017 31-01-2017 16,000/- 3200/- 19,200/-33 01-02-2017 28-02-2017 16,000/- 3200/- 19,200/-34 01-03-2017 31-03-2017 16,000/- 3200/- 19,200/-

Total 4,96,000/- 99,200/- 5,95,200/-

The total amount allocated by UGC for the salary and HRA of project fellow Rs. 5,28,000/-The total amount paid by UGC for the salary and HRA of project fellow Rs. 2,77,200/-The total amount utilized for the salary (19 months from 01-06-2014 to 31-12-2015 @14,000/- p.m.) of project fellow

Rs. 2,66,000/-

Net balance for the salary of Project Fellow Rs. 11, 200/-The payable amount for the salary (5 months from 01-01-2016 to 31-05-2016 @14,000/- p.m. and 10 months from 01-06-2016 to 31-03-2017 @ 16,000/- p.m.) and HRA( 34 months from 01-06-2014 to 31-03-2017 @ 20% of the salary) of project fellow

Rs. 3,29,000/-

The amount still pending on UGC for salary + HRA of project fellow Rs. 3,18,000/-

10

Annexure -VIIIUNIVERSITY GRANTS COMMISSION



Final Report of the work done on the Major Research Project.

1. Project report No. Final

2. UGC Reference No.: F. No. 42-780/2013 (SR), FD Diary No. 5532 dated 18-03-2014.

3. Period of report: From 01-04-2014 to 31-03-2017

4. Title of research project;

“Kinetics of first order phase transformation and Structural studies of Sb, Zn and Bi

doped Se –In chalcogenide glasses”.

5. (a) Name of the Principal Investigator: Dr. Shamshad Ahmad Khan

(b) Department. Physics

(c) University/College where work has progressed

St. Andrew’s P.G. College Gorakhpur, U. P. India

6. Effective date of starting of the project: 01-04-20214.

7. Grant approved and expenditure incurred during the period of the report:

(a) Total amount approved Rs.15,08,800/-

(b) Total amount received in first phase Rs. 11,24,800/-

(c) Total amount received in second phase Rs. 1,09,200/-

(d) Total amount paid by UGC Rs. 12,34,000/-

(e) Total expenditure Rs. 15,68,000/-

(f) Total amount due on UGC Rs. 3,34,000/-

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(c) Report of the work done:

(i) Brief objective of the project:

The study of first order phase transformation by non- isothermal DSC measurements has

become particularly prevalent for the determination of the thermal stability of amorphous

alloys. These techniques provide rapid information on such parameters as the glass transition

temperature, crystallisation temperature and the activation energy over a wide range of

temperature. Since crystallisation in some of chalcogenides glasses occurs at quite moderate

temperature, the study of phase transformation is important from the application points of

view. Such studies may be useful in predicting the switching behaviour and also for searching

suitable phase change materials for optical data.

The objective of the project was

(1) To prepare a number of binary and ternary amorphous materials by using melt

quenching method.

(2) Their amorphous nature was verified by X-ray diffraction.

(3) Non- isothermal DSC experiments was performed at different heating rates.

(4) The glass transition temperature (Tg), crystallisation temperature (Tc), melting

temperature (Tm) of these glasses were determined using the differential scanning

calorimeter at different heating rates.

(5) Phase transformation studies for these glasses were studied by using the modified

Kissinger and Ozawa model.

(6) The dependence of Tg and Tc on heating rate (β) were used for the determination of

the activation energy of crystallization (Ec), the activation energy of structural

relaxation (Et), the glass thermal stability (Tc-Tg), crystallisation enthalpy (Hc) and the

Avrami exponent.

(7) The structural studies during first order phase transformation was performed by X-ray

diffraction and SEM studies.

All the objectives of the project has been completed successfully.

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We have prepared following bulk alloys by melt quenching technique.

Compound AlloySe85In15-xSbx Se85In15

Se85In12Sb3

Se85In9Sb6

Se85In6Sb9

Se85In15-xZnx Se85In15

Se85In12Zn3

Se85In9Zn6

Se85In6Zn9

Se85In15-xBix Se85In15

Se85In12Bi3

Se85In9Bi6

Se85In6Bi9

Ga15Te85-xZnx Ga15Te83Zn2

Ga15Te81Zn4

Se75Te25-xCdx Se75Te25

Se75Te22Cd3

Se75Te16Cd9

Se75Te13Cd12

Se75Te25-xInx Se75Te22In3

Se75Te19In6

Se75Te16In9

Se75Te13In12

Ga10Se78Tl12

Ga15Se77Sb8

Ga15Se77Tl8

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List of Publications under this projectResearch papers published in international reputed journals

S.No.

Title of papers Journal ImpactFactor

1 Structural, Optical and Electrical Characterization ofPolycrystalline Ga15Te85−xZnx Nano-Structured Thin FilmsShamshad A. Khan, Gargi Tiwari, Ravi P. Tripathi, M. A.Alvi, Zishan H. Khan, F. A. Al-Agel

Advanced Science LettersVol. 20, 1715–1718, 2014

1.484

2 A study on photo-induced crystallization in Ga10Se78Tl12 thinfilmsRavi P. Tripathi, M. Shaheer Akhtar, M. A. Alvi, ShamshadA. Khan

Journal of MaterialsScience:Materials in ElectronicsVol 26, 6206-6211,2015

1.798

3 Studies on phase change Ge15Se77Sb8 thin films by laserirradiationArchana Srivastava, Ravi P. Tripathi, M. Shaheer Akhtar,Shamshad A. Khan

Journal of MaterialsScience:Materials in ElectronicsVol. 27, 1715–1718, 2016

1.798

4 Influence of annealing treatment on phase transformation ofGa15Se77Tl8 thin filmsRavi P. Tripathi, M. Shaheer Akhtar, M. A. Alvi, ShamshadA. Khan

Journal of MaterialsScience:Materials in ElectronicsVol 27, 8227-8233, 2016

1.798

5 Structural, optical and electrical properties of Se85In9Bi6

nanochalcogenide thin filmRavi P. Tripathi, M. Zulfequar, Shamshad A. Khan

Current NanomaterialsVol 1 (3), 176-182, 2016PublisherBentham Science

781ISSN(Print): 2405-

4615ISSN (Online):

2405-46236 First-order phase transformation and structural studies in

Se85In15-xZnx chalcogenide glassesArchana Srivastava, S. N. Tiwari, A.N. Upadhyay, M.Zulfequar, Shamshad A. Khan

Journal of ThermalAnalysis and CalorimetryFirst Online: 23 March 2017DOI:10.1007/s10973-017-6273-9

1.781

7 Influence of Thermal Annealing on Structural and OpticalProperties of Se85In12Bi3 Thin Chalcogenide FilmsRavi P. Tripathi, M. Zulfequar, Shamshad A. Khan

Materials FocusVol 6, 463–467, 2017

PublisherAmerican ScientificPublishers.

ISSN: 2169-429X (Print)EISSN: 2169-4303 (Online)

8 Study of thiol capped CdSe quantum dots using SeO2precursor for selenium sourceZubair M.S.H. Khan, Shamshad A. Khan, M. Julfequar

Materials science insemiconductingprocessingVol 57, 190-196, 2017

2.157

Research paper published in the conference preceding

S. No. Title of papers Conference

1 Structural, Optical and Electrical Characterization ofPolycrystalline Ga15Te85−xZnx Nano-Structured ThinFilmsShamshad A. Khan, Gargi Tiwari, Ravi P. Tripathi,M. A. Alvi, Zishan H. Khan, F. A. Al-Agel

Nat. Conf. on Nano. and Rene. Ener.held on 28-29 April 2014at Jamia MilliaIslamia, New Delhi

2 Influence of Thermal Annealing on Se75Te22Cd3 ThinFilm for Optical Data StorageRavi P. Tripathi, Vishal Singh Chandel, Shamshad A.Khan

Nat. Conf. on Func. Mat. held on 22 Oct.2016 at Department of Physics, IntegralUniversity, Lucknow

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3 Kinetics of First Order Phase Transformation inSe75Te19In6 Glass for Phase Change MemoryArchana Srivastava, S. N. Tiwari, Anis Ahmad,Shamshad A. Khan

Nat. Conf. on Func. Mat. held on 22 Oct.2016 at Department of Physics, IntegralUniversity, Lucknow

4 Synthesis and characterization of CdSe quantum dotsdispersed in PVA matrix by chemical routeZubair M.S.H. Khan, Mohsin Ganaie, Shamshad A. Khan,M. Husain, M. Zulfequar

AIP Conference Proceedings 1731, 050069(2016);doi: http://dx.doi.org/10.1063/1.4947723

Research Paper communicated in international reputed journalS. No. Title of papers Journal name

1. Crystallization kinetics and phase transformation studies in glassySe85In15-xSbx systemRavi P. Tripathi, Kedar Singh, Shamshad A. Khan

Materials Chemistry andPhysics, Ref. No.MATCHEMPHYS-D-17-01626

2. Thermally deposited Se85In15-xSbx chalcogenide thin films: Structural,Electrical and optical propertiesRavi P. Tripathi, M. Shaheer Akhtar, A. N. Upadhayay, M. Zulfequar,Shamshad A. Khan

Journal of MaterialsScience:Materials in ElectronicsSub. ID: JMSE-D-17-01861

3. Non-isothermal crystallization kinetics and structural studies duringphase transformation in Se75Te25-xInx chalcogenide glassesArchana Srivastava, S. N. Tiwari, Kedar Singh, Shamshad A. Khan

Journal of crystal growth

Paper Presented in national and international conferencesS. No. Title of papers Conference

1 Structural, Optical and Electrical Characterization ofPolycrystalline Ga15Te85−xZnx Nano-Structured ThinFilmsShamshad A. Khan, Gargi Tiwari, Ravi P. Tripathi, M.A. Alvi, Zishan H. Khan and F. A. Al-Agel

Nat. Conf. on Nano. and Rene. Ener. held on 28-29 April 2014at Jamia Millia Islamia, New Delhi

2 Influence of annealing treatment on phasetransformation of Ga15Se77Tl8 thin filmsRavi P. Tripathi, M. Shaheer Akhtar, M. A. Alvi &Shamshad A. Khan

Nat. Sem. in Curr. Tren. in Chem. Sci. held on15-16 October 2014 at Department of Chemistry,St. Andrew’s college, Gorakhpur

3 First order phase transformation in Ga10Se78Tl12 thinfilmRavi P. Tripathi, M. Shaheer Akhtar, M. A. Alvi &Shamshad A. Khan

Nat. Conf. on Eme. Tren. in Phys. and Mat. Sci.held on 9-10 March 2015 at Chaudhary DevilalUniversity, Sirsa Haryana

4 Synthesis and characterization of Se85In6Sb9 nano-chalcogenide thin filmRavi P. Tripathi, M. Husain, Shamshad A. Khan

IWPSD-2015 held on 7-9 Dec 2015 at ISCBangalore, Karnataka

5 Studies on Se85In9Sb6 chalcogenide thin films preparedby thermal evaporation techniqueRavi P. Tripathi, Shamshad A. Khan

Nat. Conf. on Func. Mat. held on 10-12 March2016 at Department of Physics, D. D. U.Gorakhpur University, Gorakhpur

6 Kinetics of crystallization in Se85In12Zn3 chalcogenideglass using non-isothermal DSC measurementsArchana Srivastava, Shamshad A. Khan

Nat. Conf. on Func. Mat. held on 10-12 March2016 at Department of Physics, D. D. U.Gorakhpur University, Gorakhpur

7 Crystallization kinetics in Se85In12Sb3 chalcogenideglasses by DSC measurementsRavi P. Tripathi, Shamshad A. Khan

Nat. Conf. on Emer. Tren. in Phys. and Mat. Sci.held on 19-20 March 2016 at Chaudhary DevilalUniversity, Sirsa Haryana

8 First order phase transformation in Se85In6Zn9

chalcogenide thin films by thermal annealingArchana Srivastava, M. Husain, Shamshad A. Khan

Nat. Conf. on Emer. Tren. in Phys. and Mat. Sci.held on 19-20 March 2016 at Chaudhary DevilalUniversity, Haryana

9 Structural, optical and electrical properties of Nat. Conf. of Emer. Tren. in Appl. Sci. held on

15

Se85In6Bi9 thin chalcogenide filmRavi P. Tripathi, Anis Ahmad , Shamshad A. Khan

23-24 September 2016 at Galgotias University,Greater Noida.

10 Phase transformation studies in Se75Te19In6

chalcogenide thin filmsArchana Srivastava, Anis Ahmad, S. N. Tiwari,Shamshad A. Khan

Nat. Conf. of Emer. Tren. in Appl. Sci. held on23-24 September 2016 at Galgotias University,Greater Noida

11 Influence of thermal annealing on Se75Te22Cd3 thinfilm for optical data storageRavi P. Tripathi, Vishal Singh Chandel, Shamshad A.Khan

Nat. Conf. on Func. Mat. held on 22 Oct. 2016 atDepartment of Physics, Integral University,Lucknow

12 Kinetics of First Order Phase Transformation inSe75Te19In6 Glass for Phase Change MemoryArchana Srivastava, S. N. Tiwari, Anis Ahmad,Shamshad A. Khan

Nat. Conf. on Func. Mat. held on 22 Oct. 2016 atDepartment of Physics, Integral University,Lucknow

13 Thickness dependent studies on Se85In9Sb6

nanochalcogenide thin filmsRavi P. Tripathi, Shamshad A. Khan

Int. Conf. on Stru. and Dyn. of Bio. held on 27-28 January 2017 at Department of Physics, D. D.U. Gorakhpur University, Gorakhpur

14 Studies on Silicon quantum dots prepared at differentsubstrate temperatureShamshad A. Khan, Archana Srivastava, Zishan H.Khan

Int. Conf. on Stru. and Dyn. of Bio. held on 27-28 January 2017 at Department of Physics, D. D.U. Gorakhpur University, Gorakhpur

15 Phase transformation studies in Se85In6Bi9

nanochalcogenide thin filmRavi P. Tripathi, M. Husain, Shamshad A. Khan

Int. Conf. on Emer. Mat. and Appl. held on 20-22February 2017 at Department of Physics,University of Allahabad, Allahabad, India

16 Observation of phase separation in Se75Te22In3 andSe75Te16In9 thin films by thermal annealingArchana Srivastava, S. N. Tiwari, Shamshad A. Khan

Int. Conf. on Emer. Mat. and Appl. held on 20-22February 2017 at Department of Physics,University of Allahabad, Allahabad, India

17 Effect of thickness on structural, optical and electricalproperties of Se85In12Bi3 nanochalcogenide thin filmsRavi P. Tripathi, M. Husain, Shamshad A. Khan

Int. Conf. on Nano. and Nanotech. held on 1-3March 2017 at Vinoba Bhave Research Institute,Saidabad, Allahabad, India

(a) Manpower trained:

The project fellow Mr. Ravi Prakash Tripathi has trained in good manner. He has

published several research papers in international reputed journals and is in the process of

writing his Ph. D. thesis and going to submit soon.

17

Annexure – IXUNIVERSITY GRANTS COMMISSION



PROFORMA FOR SUBMISSION OF INFORMATION AT THE TIME OF SENDING

THE FINAL REPORT OF THE WORK DONE ON THE PROJECT

1. Title of the project:



2. NAME AND ADDRESS OF THE PRINCIPAL INVESTIGATOR:

Dr. Shamshad Ahmad Khan

Department of Physics, St. Andrew’s College, Gorakhpur, U.P. India

3. NAME AND ADDRESS OF THE INSTITUTION:St. Andrew’s College, Gorakhpur, U.P. India

4. UGC APPROVAL LETTER NO. AND DATE:

F. No. 42-780/2013 (SR), FD Diary No. 5532 dated 18-03-2014

5. DATE OF IMPLEMENTATION 01-04-2014

6. TENURE OF THE PROJECT 01-04-2014 to 31-03-2017

7. TOTAL GRANT ALLOCATED Rs. 15,08,800/-

8. TOTAL GRANT RECEIVED Rs. 12,34,000/-

9. FINAL EXPENDITURE Rs. 15,68,000/-

Total amount due on UGC Rs. 3,34,000/-

10. TITLE OF THE PROJECT:



11. OBJECTIVES OF THE PROJECT

The study of first order phase transformation by non- isothermal DSC measurements has

become particularly prevalent for the determination of the thermal stability of amorphous

alloys. These techniques provide rapid information on such parameters as the glass transition

temperature, crystallisation temperature and the activation energy over a wide range of

temperature. Since crystallisation in some of chalcogenides glasses occurs at quite moderate

temperature, the study of phase transformation is important from the application points of

18

view. Such studies may be useful in predicting the switching behaviour and also for searching

suitable phase change materials for optical data.

The objective of the project was

(1) To prepare a number of binary and ternary amorphous materials by using melt

quenching method.

(2) Their amorphous nature was verified by X-ray diffraction.

(3) Non- isothermal DSC experiments was performed at different heating rates.

(4) The glass transition temperature (Tg), crystallisation temperature (Tc), melting

temperature (Tm) of these glasses were determined using the differential scanning

calorimeter at different heating rates.

(5) Phase transformation studies for these glasses were studied by using the modified

Kissinger and Ozawa model.

(6) The dependence of Tg and Tc on heating rate (β) were used for the determination of

the activation energy of crystallization (Ec), the activation energy of structural

relaxation (Et), the glass thermal stability (Tc-Tg), crystallisation enthalpy (Hc) and the

Avrami exponent.

(7) The structural studies during first order phase transformation was performed by X-ray

diffraction and SEM studies.

12. WHETHER OBJECTIVES WERE ACHIEVED (GIVE DETAILS)

All the objectives of the project have been achieved successfully. We have prepared the

different amorphous alloys, the nature of the alloys were verified by different tools, the first

order phase transformations in these chalcogenide glasses and thin films were verified by

different tools. We have also prepared nano-chalcogenide thin films of some of these glasses

and done their characterization using different methods. In short the conclusion is that the

prepared alloys have amorphous as well as glassy nature, from the first order phase

transformation studies we can say that these alloys have the tendency of phase transformation

so they can be used in different optoelectronic devices.

13. ACHIEVEMENTS FROM THE PROJECT

We have published 8 research papers in international reputed journals, 4 papers in conference

proceeding and presented several papers in National and International conferences.

The project fellow Mr. Ravi Prakash Tripathi has got his Ph. D. registration in March2014 and now he is writing his Ph. D. thesis and going to submit soon.

Mrs. Archana Srivastava has been registered as Ph. D. student in August 2016.

19

Eight students from M.Sc. Final year (Miss. Nidhi Singh, Miss. Jyoti Rai, Miss. Shalini

Singh, Miss. Anchal Upadhyay, Mr. Rahul Singh, Mr. Faizan Mahmood, Mr. Digvijesh

Shankar Mishra and Mr. Shivam Srivastava) and six students from M. Sc. Previous

(Miss. Pallavi Gaur, Miss. Shaista Raza, Miss. Garima Tripathi, Mr. Vindhyachal

Chaurasia, Mr. Waseeq Ahmad Khan and Mr. Abhinav Gupta) have been trained for

preparing the amorphous alloy by melt quenching technique, to operate the vacuum coating

unit, to operate DSC instrument, to characterize these alloys by means of their structural,

optical and electrical nature and they were taught about the theoretical background of these

characterizations.

14. SUMMARY OF THE FINDINGS:

The first order phase transformation in chalcogenide glasses constitutes the most promising

candidate to scale non-volatile-memory technology beyond the flash memory architecture.

These glasses can be reversibly switched between the amorphous and crystalline state and

find applications in rewritable optical recording and in electrically programmable non-

volatile memories. Phase change optical recording has evolved to a mature technology that is

applied in the re-writable versions of optical data storage systems of CD (compact disc) and

DVD (digital versatile disc). In phase-change optical recording, the recording of information

is based on writing and erasing amorphous marks in a crystalline layer of a phase change

material. Amorphous marks are written by a pulsed focused laser beam which makes the

temperature of the phase-change layer locally higher than the melting point for a short period

of time. After the pulse, the molten area is quenched to the amorphous state. Since the optical

properties of the amorphous phase are different from those of the crystalline phase, the

written mark can be read out as a contrast in the reflectance. The recorded information can be

erased by heating the material with the same focused laser beam above the crystallization

temperature but below the melting temperature. Due to the increased mobility of the atoms at

increased temperature, the amorphous state rapidly returns to the thermodynamically more

stable crystalline state. Besides sufficient optical contrast between the crystalline and

amorphous state and a sufficiently low melting point attainable with moderate laser powers,

the crystallization behavior at various temperatures is one of the most important issues in

developing phase-change materials. At elevated temperatures the crystallization rate should

be large enough to enable a high data rate. That is, in phase-change recording the maximum

rate at which previous data can be overwritten with new data is limited by the speed at which

the amorphous marks of the previous data can be erased.

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We have completed all the objectives as per the work plan of the research proposal. We have

produced 8 research papers out of these studies. We have synthesized and characterized

various phase change materials such as nano-chalcogenide Ga15Te85-xZnx thin films,

Ga10Se78Tl12 thin films, Ge15Se77Sb8 chalcogenide films, Ga15Se77Tl8 thin films, Se85In9Bi6

nano chalcogenide thin film, Se85In15-xZnx glasses, Se85In12Bi3 chalcogenide thin film,

Se85In15-xSbx, Se75Te25-xInx glasses etc.. Various studies regarding first order phase

transformation has been performed. The outcome of these studies indicates that these

materials may be suitable for various optoelectronic devices.

15. CONTRIBUTION TO THE SOCIETY

This project was dedicated to the development of phase change chalcogenide materials.

These materials are very important and will play a crucial role in future memory devices

based on phase change. We have successfully developed several phase change materials

during the course of this project. The development of the phase change materials will open up

a new direction for several industries in the field of memory devices. As our country is trying

to establish some new industries in various fields, this will provide a platform to initiate

industrialization in this upcoming field of science and technology.

Nowadays, India is a leading country in research and development point of view and

planning to manufacturer new generation solid state devices. Since amorphous chalcogenide

semiconductors have been successfully used for phase-change compact disk rewritable,

digital versatile disk rewritable, digital versatile disk-random access memory and blue-ray

disk. These glasses can be reversibly switched between the amorphous and crystalline state

and can find valuable applications in rewritable optical recording and in electrically

programmable non-volatile memories. Phase change optical recording has evolved to a

mature technology that is applied in the re-writable versions of optical data storage systems

of CD (compact disc) and DVD (digital versatile disc).

The outcome of this project is going to produce two Ph. D. students in this research field.

The project fellow Mr. Ravi Prakash Tripathi has got his Ph. D. registration in March 2014

and now he is writing his Ph. D. thesis and going to submit soon.

Mrs. Archana Srivastava has been registered as Ph. D. student in August 2016.

This research project may also be useful for the society. As we have trained several students

in this project, these students will create awareness of higher education in Indian society and

will encourage more youngsters to show their participation in higher education through

innovative research work. These research works has train several M. Sc. Physics students at

major research project - st. andrews...

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