Thin film solar cell based on CuSbS2 absorber fabricated from an electrochemically deposited metal stack

Abstract

Copper antimony sulfide (CuSbS2) thin films were fabricated by sulfurization of an electrodeposited metallic stack composed of Cu and Sb on a Mo-coated glass (Mo/glass) substrate. A CuSbS2 film containing appreciable impurity components was obtained when the precursor metallic stack was heated monotonically from room temperature to 450°C in Ar followed by sulfurization. The film also showed poor adherence due to a large number of crevices; there were many appreciable pinholes over the entire surface of the film. On the other hand, a CuSbS2 film without any impurity phases was obtained when the metallic precursor film was pretreated at 510°C in Ar for 60min just before sulfurization at 450°C. It was also observed that the thus-obtained CuSbS2 film showed good adhesion to the Mo/glass substrate and almost no notable pinholes. As expected from structural analyses, the 510°C-pretreated film worked as a relatively efficient absorber for the thin film solar cell with an Al:ZnO/CdS/CuSbS2/Mo/glass structure: it gave preliminary conversion efficiency of 3.1%.