Electrical and Photovoltaic Properties of CdS-Si Junctions

Abstract

CdS-p·Si and CdS-n·Si junctions are prepared by vacuum evaporation of CdS on Si crystals, and their electrical and photovoltaic properties are studied. The junction prepared on hot Si substrate (substrate temperature; 150°–250°C) has properties of hetero-junction, while the one on cold substrate (50°–80°C) shows properties resembling those of Schottky barrier. CdS-p·Si junctions are generally superior to CdS–n·Si junctions in rectifying properties. CdS–p·Si cell on cold substrate shows excellent photovoltaic effect which is comparable to that of Si solar cell. The maximum solar conversion efficiency of CdS-p·Si cells is about 5.5%. Here, the CdS layer is supposed to act as a semi-transparent electrode.