Effect of substrate temperature on the physical properties of co-evaporated Sn2S3 thin films

We report the deposition of tin sulfide (Sn2S3) thin films by co-evaporation technique at different substrate temperatures. The influence of substrate temperature on the structural and optical properties of the thin films is investigated. X- ray diffraction (XRD) analysis and Micro-Raman studies confirm the formation of Sn2S3 phase. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) are used to examine the surface morphology. The transmission spectra of the deposited Sn2S3 thin films have been recorded in the wavelength range of 200–3000 nm using UV–vis-NIR spectrometer. Film thickness (d) and optical constants such as refractive index (n), extinction coefficient (k), real (ε1) and imaginary (ε2) parts of the dielectric constants of thin films are estimated from the optical transmittance. The optical band gaps of the deposited films at different substrate temperatures are in the range of 1.46–1.64 eV. Hall effect measurements confirm the n-type nature of the as-prepared Sn2S3 thin films.