Cu-Ternary Chalcopyrite Solar Cells

This paper deals with solar cells based on the Cu-ternary compounds and, in particular, with CuInSe//2. It is one of only three systems which in thin film form have yielded device efficiencies greater than 10%. The advantages offered by the Cu-ternaries are discussed. These include a nearly ideal energy gap, a high optical absorption coefficient, the possibility of either p- or n-type doping, and a good match of the crystal lattices and affinities of the Cu-ternaries with typical window-layer materials. The structure and composition of the materials plus the methods used for the production of single crystals and thin films are discussed in detail. A similar presentation of the optoelectronic properties is given, and the authors point out several of the anomalies which exist. The final sections of this chapter are concerned with analysis of actual devices based on the Cu-ternaries and on interfacial properties between the various layers. Finally, pointers for future development are given.