Optical properties of spin-coated SnS2 thin films

This paper reports optical properties of n-type SnS2 thin films, prepared by spin-coating of a sol-gel based on the lowcost and environmentally friendly solvent dimethyl sulfoxide (DMSO). The effect of a short-term low-temperature treatment in air and final annealing under low vacuum (0.1 Pa) on the synthesis of tin disulfide films was tested and analyzed. The dynamics of changes of optical properties of the films on the parameters of spin-coating and heat treatment was established. The value of the band gap Eg ≈ 2.25 – 2.54 eV for SnS2 and Eg ≈ 1.99 eV for Sn2S3 was determined from the analysis of optical characteristics.