Development of thin‐film Cu(In,Ga)Se₂and CdTe solar cells

Abstract Cu(In,Ga)Se 2 and CdTe heterojunction solar cells grown on rigid (glass) or flexible foil substrates require p ‐type absorber layers of optimum optoelectronic properties and n ‐type wide‐bandgap partner layers to form the p –n junction. Transparent conducting oxide and specific metal layers are used for front and back electrical contacts. Efficiencies of solar cells depend on various deposition methods as they control the optoelectronic properties of the layers and interfaces. Certain treatments, such as addition of Na in Cu(In,Ga)Se 2 and CdCl 2 treatment of CdTe have a direct influence on the electronic properties of the absorber layers and efficiency of solar cells. Processes for the development of superstrate and substrate solar cells are reviewed. Copyright © 2004 John Wiley & Sons, Ltd.