EE143 F2010 Lecture 26 Solar Cells Fabrication Technologies Crystalline Si Cell Technologies Amorphous Si Cell Technologies Thin Film Cell Technologies For a comprehensive tutorial on solar cells in general see www udel edu igert pvcdrom Professor N Cheung U C Berkeley 1 EE143 F2010 Lecture 26 Global Energy Sources projection Source World Energy Council Professor N Cheung U C Berkeley EE143 F2010 Lecture 26 The Growth Rate Captures the Attention Professor N Cheung U C Berkeley Source AMAT 3 EE143 F2010 Lecture 26 Solar Facts The earth receives more energy from the sun in just one hour than the world uses in a whole year 1 of the land today used for crops and pasture could supply the world s total energy consumption The Sun provides 1020 Watts meter peak power at sealevel Cell efficiency of 10 translates to 100W meter2 Professor N Cheung U C Berkeley EE143 F2010 Lecture 26 Commonly Known Solar Cell Materials Professor N Cheung U C Berkeley EE143 F2010 Lecture 26 Fraunhofer Professor N Cheung U C Berkeley EE143 F2010 Lecture 26 Beside efficiency there are other considerations for ultilization Professor N Cheung U C Berkeley 7 EE143 F2010 Lecture 26 Projected Module Cost Professor N Cheung U C Berkeley EE143 F2010 Lecture 26 Energy Content EG silicon Solar Grade Si MG silicon 200 kWh kg 50kWh kg 20kWh kg Energy Payback time Monocrystalline Si cell Polycrystalline Si cell Amorphous Si cell 4 years 1 6 to 2 7 years 0 9 to 1 6 years Richard Corkish Solar Progress 1997 9 Professor N Cheung U C Berkeley EE143 F2010 Lecture 26 Comparison of commercial PV Crystalline Amorphous Silicon Silicon Conversion Efficiency 13 18 CIGS CdTe Organic 5 10 10 12 10 5 5 1 3 1 predict Current cost per Watt 2 5 3 5 2 2 5 0 6 predict Material Shortage No Silane Indium Te No Toxic Substance NA NA Cadmium Selenium Cadmium Tellurium NA Reliability Excellent Fair Good Good Poor Company in Suntech the field SunPower AMAT Dupont Nanosolar First Solar Solyndra Konarka 10 Professor N Cheung U C Berkeley EE143 F2010 Lecture 26 Si Crystalline Solar cells are just large area semiconductor diodes Crystalline solar cells are usually wafers about 0 3 mm thick sawn from Si ingot 15 efficiency cells deliver 15 to 60 W m or 0 45 1 35 kWh m day annual day and night average in North America Professor N Cheung U C Berkeley EE143 F2010 Lecture 26 From Ingot to Module Professor N Cheung U C Berkeley 12 EE143 F2010 Lecture 26 From Ingot to Module cont Professor N Cheung U C Berkeley 13 EE143 F2010 Lecture 26 From Sand to Silicon Process generates four tons of silicon tetrachloride liquid waste for each ton of polysilicon produced 14 Professor N Cheung U C Berkeley EE143 F2010 Professor N Cheung U C Berkeley Lecture 26 15 EE143 F2010 Professor N Cheung U C Berkeley Lecture 26 16 EE143 F2010 Lecture 26 Minimize Kerf Loss Professor N Cheung U C Berkeley 17 EE143 F2010 Lecture 26 Generic Crystalline Si Cell Processing Al Ag paste Al Ag fuses through SiNx to form ohmic contact Professor N Cheung U C Berkeley 18 EE143 F2010 Lecture 26 Backside Al contact BSF back surface field p layer Professor N Cheung U C Berkeley 19 EE143 F2010 Lecture 26 Belt Furnace Max T 950C Professor N Cheung U C Berkeley 20 EE143 F2010 50 MW fab cell line Source Applied Materials Professor N Cheung U C Berkeley Lecture 26 EE143 F2010 Professor N Cheung U C Berkeley Lecture 26 22 EE143 F2010 Professor N Cheung U C Berkeley Lecture 26 23 EE143 F2010 Professor N Cheung U C Berkeley Lecture 26 24 EE143 F2010 Lecture 26 Antireflection Coating Materials Professor N Cheung U C Berkeley 25 EE143 F2010 Lecture 26 Diagnosis of Crystalline Silicon Solar Cells Utilizing Electroluminescence save production costs by sorting out defective solar cells in an early stage Professor N Cheung U C Berkeley 26 EE143 F2010 Lecture 26 Module Packaging Source Spire Corp Professor N Cheung U C Berkeley 27 EE143 F2010 Lecture 26 Crystalline Si on Glass CSG Solar Cell All fabrication done with Laser processing and low temperature PECVD Professor N Cheung U C Berkeley EE143 F2010 Lecture 26 Sliver Cell A wafer assume 150mm diameter configured as a conventional solar cell has an area of 177cm2 However the same wafer when processed to produce Sliver cells can be used to cover up to 5 000 cm2 of module area which is 30 times better than for conventional technology Professor N Cheung U C Berkeley 29 EE143 F2010 Lecture 26 Motivation for amorphous Si Cell Both silicon and thin film PV solutions require a reduction in cost watt Source Applied Materials Professor N Cheung U C Berkeley EE143 F2010 Lecture 26 Rigid and Flexible a Si Solar Cells 30 T Ag n a Si H i a Si H Glass p aSiC H ZnO Textured TCO Glass TCO p i n Ag Opaque SS Kapton SS ZnO p i n Ag Voc Doped layers Jsc i layer defect density Light trapping FF i layer defect density Professor N Cheung U C Berkeley Cell efficiency h Voc Jsc FF Pin EE143 F2010 Lecture 26 Amorphous Si Deposition Professor N Cheung U C Berkeley 32 EE143 F2010 Lecture 26 Amorphous Si Deposition Professor N Cheung U C Berkeley 33 EE143 F2010 Lecture 26 a Si Cell Manufacturing Source ULVAC Solar Professor N Cheung U C Berkeley 34 EE143 F2010 Lecture 26 Conceptual a Si Cell Fab Source AMAT Professor N Cheung U C Berkeley 35 EE143 F2010 Professor N Cheung U C Berkeley Lecture 26 EE143 F2010 Lecture 26 CIGS Solar Cells Professor N Cheung U C Berkeley 37 EE143 F2010 Professor N Cheung U C Berkeley Lecture 26 38 EE143 F2010 Lecture 26 CIGS Manufacturing Source pmc org tw Professor N Cheung U C Berkeley 39 EE143 F2010 Professor N Cheung U C Berkeley Lecture 26 40 EE143 F2010 Professor N Cheung U C Berkeley Lecture 26 41 EE143 F2010 Professor N Cheung U C Berkeley Lecture 26 42 EE143 F2010 Lecture 26 Roll to Roll Manufacturing Source Ascent Solar Professor N Cheung U C Berkeley 43 EE143 F2010 Professor N Cheung U C Berkeley Lecture 26 44 EE143 F2010 Lecture 26 Needs MBE MOCVD or Layer Transfer Professor N Cheung U C Berkeley 45 EE143 F2010 Lecture 26 c Si thin film New Concepts Technology Evolution MW 3500 GW 140 25 p a 30 p a 3000 120 2500 100 2000 80 1500 60 1000 40 500 20 0 2002 2005 2010 2015 2020 2025 2030 0 RENEWABLE ENERGY FOR EUROPE RESEARCH IN ACTION Professor N Cheung U C Berkeley 46 EE143 F2010 Lecture 26 Q What are the major differences between PV fabrication and IC MEMS fabrication Patterning alignment size control Doping Contact Formation Metallization Planarization Q What other process modules are not commonly used in IC MEMS fabrication Professor N Cheung U
View Full Document
Unlocking...