Influence of Sn/S composition ratio on SnS thin-film solar cells produced via co-evaporation method

SnS thin films were fabricated using a co-evaporation method, and the optimization of SnS thin films in terms of substrate temperature and the dependence of their properties on Sn/S ratio were investigated. The substrate temperature was adjusted in the range of 250-350 degrees C. On the other hand, the SnS thin films with Sn/S compositional ratios of 0.88-1.28 were fabricated. The resulting SnS films were then used to fabricate solar cells with the structure glass/Mo/SnS/CdS/ZnO: Al/Al. It was found that the optimal substrate temperature for SnS thin films was 300 degrees C. The highest performance was obtained for solar cells containing a SnS thin film with a Sn/S ratio that was slightly lower than the stoichiometric value. (C) 2018 The Japan Society of Applied Physics