Large-area CIGS absorbers prepared by physical vapor deposition

An in-line process for deposition of Cu(In,Ga)Se2 (CIGS) films on 10×10 cm2 substrates has been developed in order to fabricate high-efficiency CIGS modules. At the first step, CIGS solar cells with a small area were fabricated by the in-line evaporation. The cells on different positions in 10×10 cm2 area showed almost the same efficiency of over 14%. Twelve cells on a substrate of 5×10 cm2 size showed an average efficiency of about 13%. Device-quality CIGS films can be prepared by the in-line evaporation. Furthermore, interconnected CIGS submodules were fabricated on 10×10 cm2 size substrates. The CIGS submodule has achieved an efficiency of 10.5%. The segmental cells in the submodule showed an average open-circuit voltage higher than 0.6 V, comparable to that of a high-efficiency cell with a laboratory size.