Study of Substrate Temperatures Effects on the Properties of Ultrasonically Sprayed SnS2 Thin Films

Abstract

Tin disulfide (SnS2) thin films have drawn worldwide attention because of their outstanding performance and earth-abundant constituents. However, problems such as coexistence of complex secondary phases (SnS, Sn2S3), the band tailing issue, and bulk defects need to be addressed for further efficiency improvement. In this regard, the present work is intended for the treatment of one of these problems. Herein, a single phase SnS2 has been obtained using an ultrasonic spray pyrolysis method. which is confirmed by X-ray diffraction (XRD) and energy dispersive X-rays (EDXs) characterization techniques. The substrate temperatures (Ts) were increased from 250 °C to 450 °C, and this significantly improved the film's characteristics, which varied from an amorphous phase and a mixture of crystalline phases, SnS2 and SnS (for the films obtained at Ts = 250 and 300 °C) to a SnS2 pure phase with a hexagonal structure (for Ts ≥ 350 °C). The morphological, optical, and electrical properties of SnS2 films are greatly improved by temperature increases too, especially for the film obtained at 450 °C. This suggests that there are opportunities for further efficiency by using the as-deposited SnS2 thin film at 450 °C.