LAUSR

Abstract We used thermal evaporation and post-deposition thermal treatment to prepare photoconductive Ag-Sb-S thin films. Firstly, to obtain the Ag2S/Sb2S3/substrate samples, we sequentially evaporated both Sb2S3 and Ag2S precursors. Secondly, we converted the double-layered structure in Ag-Sb-S thin films through a post-annealing treatment. Finally, considering the variation in both temperature of this treatment and amount of evaporated Ag2S, we evaluated the formation of AgSbS2 and Ag3SbS3 ternary phases in the films. As a result, we identified the coexistence of cubic and monoclinic AgSbS2 and monoclinic and hexagonal Ag3SbS3 phases. In addition, the evolution from metastable to stable phases of AgSbS2 and Ag3SbS3 is presented. Using Raman vibrational modes at 267 cm-1 for the monoclinic and 323 cm-1 for the hexagonal phases and X-ray diffraction results, we identified the dominant Ag3SbS3 crystalline structure. Furthermore, we found that, respectively, the optical band gap, electrical conductivity and photosensitivity are in the range of 1.7–1.85 eV, 1.3 × 10-7 to 7.4 × 10-5 (Ω-cm)-1 and 29 to 0.5. Consequently, the Ag-Sb-S thin films are suitable as the absorber layer in photovoltaic solar cells.