Structural and optical studies of chemically deposited Sn2S3 thin films

Sn2S3 thin films were grown on commercial glass substrates by chemical bath deposition at room temperature. The structural and optical properties of Sn2S3 thin films were studied as a function of deposition time. The thin films were characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM) and UV–vis spectroscopy. The XRD pattern showed that the Sn2S3 thin films had an orthorhombic polycrystalline structure. The lattice constants of the thin films were a = 8.741 Å, b = 14.034 Å and c = 3.728 Å. The characteristic bonds of Sn2S3 were observed at 66.3, 111.7, 224.7 and 308.9 cm−1 using Raman shift experiment. The optical energy band gap of the thin films decreased from 2.12 eV to 2.03 eV with increasing deposition time from 20 to 24 h. The optical constants of the thin films were obtained using the experimentally recorded transmission data as a function of the wavelength.