Optical and Electrical Properties of Sb2(SxSe1–x)3 Films for Solar Cells

Abstract

The vacuum thermal evaporation method was used to produce Sb₂(S_xSe_1–x)₃ films from powders of precursor binary compounds, Sb₂S₃ and Sb₂Se₃, at substrate temperature 300°C. The effect of the elemental composition ratio S/(S + Se) on the optical and electrical properties of Sb₂(S_xSe_1–x)₃ films was studied. The band gap width of Sb₂(S_xSe_1–x) films increases with an increase in the sulfur concentration. The prepared films feature low Urbach energies indicating low-defect structure. The temperature dependence of the resistance indicated the presence of deep-lying levels in the range 0.5–0.8 eV depending of the S/(S+Se) atomic concentration ratio. These results indicate the feasibility of producing effective solar cells containing Sb₂(SxSb_1–x)₃ obtained by means of thermal evaporation of powders of Sb₂S₃ and Sb₂Se₃.