Let me give some introduction about CIGS before starting discussion.
CIGS stands for Cu(In,Ga)Se2 which acts as absorber layer and CdS can be used as buffer layer in this solar cell. The layered cell structure is ZnO/CdS/CIGS/Mo/soda-lime glass or flexible substrate. CIGS solar cell with record 19.9% total-area efficiency demonstrated at the National Renewable Energy Laboratory (NREL) and is a promising candidate to replace silicon solar cells.
Major challenges in the area is to find cost effective technique for the film deposition and to achieve grain growth in CIGS without toxic selenization step.
Some of the major companies working in this area are Global solar, Nanosolar, ISET, Daystar, Solarpower and many more. Most of the companies follow co-evaporation technique for film deposition.
Please express your insight, updates and ideas in this field to find solution on energy problem.
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