Cadmium and Zinc Chloride Treatments of CdS Films for the Preparation of High Efficiency CdTe/CdS Thin Film Solar Cells

CdTe/CdS thin film solar cells exhibiting conversion efficiency dose to 14% have been prepared on glass substrates by treating the CdS film with ZnCl2 and CdC2. This treatment has shown to be effective in rendering the CdS film less reactive with CdTe when this is deposited on top of CdS by Close Spaced Sublimation at a substrate temperature of 500-520°C. This limits the interdiffusion between CdS and CdTe during the cell preparation and improves both the open-circuit voltage and fill factor of the solar cell