CdS: characterization and recent advances in CdTe solar cell performance

Cadmium sulfide (CdS) films deposited by chemical bath deposition (CBD) have been used for the fabrication of high efficiency CdTe and CuIn/sub 1-x/Ga/sub x/Se/sub 2/ thin film solar cells. An attractive alternative deposition technology with manufacturing advantages over the CBD is the close spaced sublimation (CSS). In this work CdTe/CdS solar cells prepared entirely by the CSS exhibited 15.0% efficiencies under global conditions as verified at the National Renewable Energy Laboratory. This paper reports on studies carried out on as deposited and heat treated CSS CdS films and all CSS CdTe/CdS solar cells using photoluminescence, X-ray diffraction, and I-V-T measurements.