The influence of posttreatment processes on the structures and the optical and electrical properties of CuInS2 and its heterojunction with various sulfides (CdS, CdZnS, and CdCuS)

• Published in: Journal of sol-gel science and technology 2021-03, Vol.97 (3), p.672-684
• Main Authors: Gu, Junjie, Ying, Ming, Zhao, Yue
• Format: Article
• Language: English
• Subjects: Bromine; Cadmium sulfide; Ceramics; Chalcopyrite; Chemistry and Materials Science; Composites; Current density; Deposition; Electrical properties; environment and building applications; Etching; Evaporation; Glass; Heterojunctions; Inorganic Chemistry; Materials Science; Methanol; Nanotechnology; Natural Materials; Optical and Electronic Materials; Optical properties; Original Paper: Sol-gel and hybrid materials for energy; P-n junctions; Photoelectric effect; Photoelectric emission; Photoelectricity; Photovoltaic cells; Saturation; Solar cells; Thin films
• ISSN: 0928-0707; 1573-4846
• DOI: 10.1007/s10971-021-05473-6

s As the first essential step toward understanding how to obtain an efficient CuInS 2 -based solar cell, this paper studied the photoelectric properties of CuInS 2 and sulfide P–N heterojunction. For this purpose, the single-source evaporation method and the chemical bath deposition had been applied to prepare CuInS 2 films and sulfide films (CdS, CdZnS, and CdCuS), respectively. The powder source was obtained from CuInS 2 polycrystalline ingot, which consists of CuInS 2 chalcopyrite phase. The segregated Cu x S secondary phase on the surfaces of CuInS 2 films could be removed by etching of bromine–methanol (BM) solution. The structures of ternary sulfide films (CdZnS and CdCuS) were similar to that of CdS film. The transient photocurrent of CdZnS thin film was highest, which might be related to the high reaction activity and the good crystal quality. Furthermore, the I – V response of CuInS 2 and CdZnS heterojunction was studied, which was close to the ideal diode type behavior. The low reverse saturation current density, the optimal diode ideality factor, and the high barrier height were obtained from the I – V curve of CuInS 2 and CdZnS heterojunction, which might mean that the CdZnS film could be suitable to use in photovoltaic application. The opening voltage of the I – V curve was related to CdZnS film the steepest, showing remarkable rectification characteristic. Highlights The single source evaporation method and the chemical bath deposition had been applied to prepare CuInS 2 films and sulfide films (CdS, CdZnS and CdCuS), respectively. The segregated CuxS secondary phase on the surfaces of CuInS 2 films could be removed by etching of Bromine Methanol (BM) solution. The low reverse saturation current density, the optimal diode ideality factor and the high barrier height were obtained from the I-V curve of CuInS 2 and CdZnS heterojunction.