Effect of Organic Solvent on the Physical Properties of Spin-Coated Tin Sulfide Thin Films

Abstract

In the current study, the sol-gel spin coating was used to deposit SnS thin films on ordinary glass substrates, and annealed without sulfurization at 500 °C. Different organic solvents such as ethanol, 2-methoxyethanol, and methanol were used and their influence on the properties of SnS thin films was investigated. X-ray diffraction showed that the three prepared films have an orthorhombic structure with preferred orientation along (111) plan. In addition, the obtained films from ethanol solvent present better crystallinity with larger grain sizes around to 28.19 nm. Morphological and compositional analysis was obtained with a scanning electron microscope associated with an X-ray spectrometer. The results show better texture with uniform coverage on the glass substrate of the deposited films obtained for ethanol as solvent. The optical analysis obtained from the UV–vis spectrophotometer reveals that the deposited films show a broad absorption spectrum in the visible region and the band gap was found to lie in the range of 1.51 to 1.95 eV. The four-points probe measurement revealed smaller electrical resistivity for the films obtained from ethanol 1.76 × 10²(Ω.cm) and a higher conductivity 5.68 × 10⁻³(Ω.cm)⁻¹.