CIGS solar cells on flexible stainless steel substrates

Flexible solar cells are useful for many situations such as curved surfaces, mobile devices, space uses, etc. The authors have developed flexible Cu(In,Ga)Se/sub 2/ (CIGS) solar cells with stainless steel substrates. CIGS films were deposited by an in-line evaporation system. The CIGS films have strong adhesion to Mo films. The phases of CIGS films on the stainless steel and on the glass had almost the same patterns, but grain sizes of CIGS films on the Mo/stainless steel are smaller than those of the films on the glass. A device efficiency of 12.2% was achieved by the flexible CIGS solar cell with the stainless steel substrate.