Ternary Semiconductor AGS Thin Films

A very challenging technology is based on the ternary compound semiconductors: CIS CGS AIS AGS and their multinary alloys. It became evident that CIS process technology is very flexible with respect to process conditions. Establishing a well-controlled system for multisource coevaporation by Boeing made the CIS cell soon the front-runner with respect to thin-film solar cell efficiencies. In later developments the addition of Ga helped to increase the efficiency. One of the problems with CIS is that its band gap energy is somewhat low to match the optimum solar spectrum. Apart from that copper causes shorting effects in photovoltaic device due to its larger diffusion coefficient. It was observed in our research work that inclusion of Ga causes increase in band gap energy in CIS. Hence copper and indium of CIS has been replaced by silver and gallium respectively in AGS to get rid of the inherent problems of CIS. This book addresses the analysis of growth and characterization of the AGS thin films with a view to assessing their suitability for utilization in photovoltaic devices like absorber materials in solar cell fabrication.