2012 11-27-masterclass-conductive-inks-acreo
DESCRIPTION
Masterclass conductive printingTRANSCRIPT
Peter Dyreklev Acreo AB
CLIP WORKSHOP 27 NOVEMBER
2012
www.acreo.se
ACREO • Swedish research Institute • R&D
Broadband Technology Fiber Optics Nanoelectronics Printed Electronics Sensor Systems
www.acreo.se
PRINTED ELECTRONICS TO MEET CHALLENGES
• Motivation
• Strategy
• Technology
www.acreo.se
PEA A THIRD OF ALL FOOD THAT IS PRODUCED IS NEVER EATEN….
• In total 1 billion tons per year is wasted! • Huge amount of green house gases is released to no use! • In industrialized countries a great part is wasted by consumers!
From the report “Global food losses and food waste” (May 2011)
www.acreo.se
MORE THAN 30% OF ALL MEDICINES ARE FAKE ACCORDING TO WHO….
Black Market Product Rankings : 1.Counterfeit Drugs$200 Billion 3.Counterfeit Electronics$169 Billion 4.Marijuana$141.80 Billion 12.Counterfeit Foods$49 Billion 13.Counterfeit Auto Parts $45 Billion 14.Counterfeit Toys$34 Billion 25.Counterfeit Clothing$12 Billion 34.Counterfeit Cosmetics$3.0 Billion 36.Counterfeit Aircraft Parts $2 Billion 40.Fake Diplomas and Degrees$1 Billion 44.Counterfeit Pesticides $735 Million 46.Counterfeit Money $ $182 Million 48.Counterfeit IDs and Passports $100 Million
Losses to Counterfeit Goods by Country: 1.United States$225 Billion 2.Mexico$75 Billion 3.Japan$75 Billion 4.China$60 Billion
www.acreo.se
WEE NEED SOLUTIONS FOR BETTER USE OF OUR LIMITED RESOURCES!
We need solutions for increased security!
We need solutions for moving health care to home environment!
www.acreo.se
Transistors Diodes Displays Interconnects/ Antennas
Printed components developed by Acreo
• Making components Displays Transistors Diodes Sensors Antennas
• Integration into printed systems • Hybrid solutions with Si-chips
Printed electronics offer a possibility to meet these challenges
www.acreo.se
PRINTING FOR FUNCTIONALITY What is required for functional materials in general
• High resolution (better than 200 µm line width and space) • Good registration (better than 50 µm registration accuracy
between layers) • Sharp line edges • Small variations in printed height • No pin holes • Thickness control • Low surface roughness • Suitable surface energy depending on type of ink • Not all printing technologies are amenable
www.acreo.se
PRINTED ELECTRONICS REQUIREMENTS – ELECTRICAL PROPERTIES
Rs = 100 mΩ/sq and thickness 5 µm corresponds to 3% of bulk conductivity value
Resistance
Conductor Width/length
Sheet resistance
Antenna Rs < 100 mΩ/sq Interconnects Rs ~ 1-100 Ω/sq
www.acreo.se
HOW TO ACHIEVE THE CONDUCTOR?
Bulk metals ~mΩ/sq for ~10 um thickness Carbon paste 10-100 Ω/sq for ~10 um thickness Conducting polymers 10-100 Ω/sq for ~10 um thickness
Metal ink is needed
www.acreo.se
DIFFERENT OPTIONS FOR METAL INK
Organometallic precursor
Flakes
Microparticles Nanoparticles
Screen printing
Flexo printing
Thermal curing
Photo curing
Ink type Inkjet Screen Flexo Thermal curing
Photo curing
Flakes (~5-10µm) No Yes No Yes No
Microparticle (~1-5µm) No Yes Yes Yes No
Nanoparticles (<0.1µm) Yes Yes ? Yes Yes
Precursor (solution) Yes ? ? Yes No
Inkjet printing
www.acreo.se
CHALLENGES FOR PRINTING OF CONDUCTORS
Does not tolerate Small register errors Breaks in narrow lines Uneven surface covering Rough substrates
Some existing printing technologies are not easily used
Continuous lines Spaces without short circuit Step coverage
www.acreo.se
LINE/SPACE INTEGRITY
Different printing methods offer various line/space performance.
www.acreo.se
LINE/SPACE INTEGRITY
200x500 500x200
Design file
Printed result
www.acreo.se
LINE/SPACE INTEGRITY
100x500
Design file
Printed result
500x100
www.acreo.se
STEP COVERAGE Large topography Bad step coverage
www.acreo.se
COMMERCIAL EXAMPLES SCREEN INKS
17
Company Ink name Ink type Curing temp/time Curing technology
resistivity [µΩ.cm] % bulk
Novacentrix Metalon HPS-021 Ag-flake 150C/30 min hot air /photonic 5 30%
TOYO-ink REXALPHA RA FS 005 Ag binder hot air 20 8% TOYO-ink REXHALPHA Radiation cure Ag binder UV 50 3% Johnson Matthey S-50 Ag binder 120/20min hot air 25 6% SUN 26-8204 (T39) Ag binder 120C/20 min hot air 30 5% SUN CRSN2442 (T246) Ag binder 150C/30min hot air 25 6% Dupont 5000 Ag binder 140C/1-1,5 min hot air 38 4%
Dupont copper ink CB200 micro copper binder 160C/30min hot air 50 3%
IIMAK Metallograph IIMAK IINK-SSC Ag coated Cu flakes (<10% Ag) 2-7 min/70 C hot air 93 2%
Advanced Nano products DGP Ag nano 120-150 C hot air 10 16% Agfa-Gevaert Agfa silver ink Ag nano 150 C/30 min hot air 5 29% IIMAK Metallograph IIMAK IINK-SSX Ag nano 2-7 min/70 C hot air 29 5%
PCHEM PSI-211 Conductive Screen Ink Ag-nano WB 140 C/15-90 sec hot air 9 18%
Ink-Tec TEC-PA-010 Ag hybrid 120-170/2-5min hot air 6 27% Novacentrix Metalon ICI-021 nano CuO Photonic Intrinsic Materials Intrinsic CP-001 Cu nano Photonic 8 20%
www.acreo.se
COMMERCIAL EXAMPLES FLEXO INKS
18
Company Ink name Ink type Curing temp/time Curing technology
resistivity [µΩ.cm] % bulk
Novacentrix Metalon HPS-021 Ag-flake 150C/30 min hot air /photonic 5 30%
TOYO-ink REXALPHA RA FS 005 Ag binder hot air 20 8% TOYO-ink REXHALPHA Radiation cure Ag binder UV 50 3%
Few conductive inks for Flexoprinting
www.acreo.se
PROCESSING CHALLENGES • Printing conductive inks is possible in standard printing equipment • A range of conductive inks are available • Drying and curing to get the low sheet resistance is crucial • Thermal curing possible
• Requires usually higher T than used in printing industry • Long drying/curing times gives low production speed
Even drying time 2 min Long ovens at reasonable speeds • Photonic curing is required for short curing time
• Requires more expensive inks – nano particles • Photonic Curing allows short curing time (~ms) High printing speed
Low cost ink necessary!
www.acreo.se
PRINTING COST Example: RFID antenna, 12,7 cm2 Screen printing 10 m/min Ag-nano ink (thermal cured) Total production cost 0,153 €/pc Ink cost only 0,137 €/pc Limited cost reduction from increased production speed or machine costs Cu nano / micro ink (photonic curing) Total production cost 0,101 €/pc Ink cost only 0,085 €/pc Large saving (~33%) possible from ink costs CLIP approach!
www.acreo.se
SUMMARY • Conductive printing possible with existing screen and flexo printing
tools • Drying and curing need to be addressed • Ink costs can be very high to get the lowest sheet resistance • Design of pattern to be printed is crucial for the end result • Range of applications can be widened with low cost inks
• CLIP gives a combination of low cost inks and higher production
speed
www.acreo.se