The effect of substrate temperature and Sn/Se mass ratio on the co-evaporated SnSe thin film for photovoltaic application

• Published in: Vacuum 2020-07, Vol.177, p.109343, Article 109343
• Main Authors: Li, Zeng, Guo, Yixin, Zhao, Fei, Nie, Chengqi, Shi, Jingyu, Liu, Xiaohui, Zuo, Shaohua, Jiang, Jinchun
• Format: Article
• Language: English
• Subjects: Co-evaporation; Conversation efficiency; Sn/Se mass ratio; SnSe thin films; Substrate temperature
• ISSN: 0042-207X; 1879-2715
• DOI: 10.1016/j.vacuum.2020.109343

In this work, SnSe thin films were prepared by co-evaporation method with different Sn/Se mass ratio and substrate temperature. The composition, structure, morphology and optical properties of the film were researched. The characterized results show that the film has a relatively pure SnSe phase under Sn/Se mass ratio of 1.50, and the crystallinity of SnSe thin films increases with the increase of substrate temperature. All the films showed p-type conductivity with a minimum resistivity of 1.96 × 10−2 Ωcm and maximum electron mobility of 24.8 cm2V−1s−1. Finally, SnSe solar cells with a device structure of soda-lime glass/Mo/SnSe/CdS/i-ZnO/ITO/Ni/Al were fabricated and a best power conversation efficiency of 0.89% was achieved at the optimum substrate temperature and Sn/Se mass ratio. These results guide high quality SnSe thin films growth and contribute to the development of efficient SnSe solar cell by using evaporation based method. •A relatively pure SnSe phase film was obtained when Sn/Se ratio is 1.50•The grain size increases with the increasing substrate temperature.•A minimum resistivity of 1.96 × 10−2 Ωcm was obtained.•A maximum electron mobility of 24.8 cm2V−1s−1 was obtained.•A best power conversation efficiency of 0.89% was achieved.