Vapor chloride treatment studies of CdTe/CdS solar cells

The most commonly used processing step for the fabrication of CdTe thin film solar cells is a heat treatment in the presence of CdCI/sub 2/. This paper discusses results on the effect of a vapor CdCI/sub 2/ heat treatment on the characteristics of thin film CdTe/CdS solar cells. The heat treatment was carried out in three different ambient environments, He, O/sub 2/, and H/sub 2/, and over a wide range of temperatures. Best solar cell performance to-date was achieved for cells heat-treated in the presence of O/sub 2/. Solar cells heat-treated in He and H/sub 2/ exhibited lower ff's and Voc's respectively. The process was optimized for high throughput and demonstrated state of the art Voc's and ffs for short annealing times.