Investigation of band gap energy versus temperature for SnS2 thin films grown by RF-magnetron sputtering

Abstract

SnS2 thin films grown by magnetron sputtering technique were characterized by structurally and optically in the present work. Crystalline parameters, atomic compositions, and surface characteristics of SnS2 thin films were presented according to results of applied structural techniques. Optical studies of SnS2 thin films were accomplished by Raman spectroscopy and transmission methods. Raman spectrum exhibited two modes around 198 and 320 cm?1. Transmittance data obtained for various temperatures between 10 and 300 K were analyzed to reveal various optical characteristics like band gap energy, variation rate of gap energy with temperature, average phonon energy, gap energy at absolute zero. Band gap energy of SnS2 thin films were reported as 2.18 and 2.22 eV at 300 and 10 K, respectively. The temperature-band gap energy dependency was analyzed taking into account the Varshni and O'Donnell-Chen models. © 2020 Elsevier B.V.