The Effect of Molarity on some Physical Properties of In₂S₃ Thin Films Deposited by Chemical Spray Pyrolysis Technique

Abstract

In2S3 thin films were grown by the chemical spray pyrolysis (CSP) method using indium chloride and thiourea as precursors at a different molar ratio (0.05, 0.1, 0.15 and 0.2)M. The deposition was carried out at 400 °C on glass substrates. The film thickness is about 0.4 μm. The X-ray diffraction analysis revealed that all the films were polycrystalline in nature with a strong (311) plane as the preferred orientation and consisted of cubic phases. The evaluated crystallite size varied in the range of (7.32–8.32) nm with the increase of molarity concentration. Morphological analysis showed that the granular structure and the granular density decrease with the raise of molarity concentration. The optical properties of the layers were also investigated using UV-Vis. analysis, which indicated that all the In2S3 films had the optical transmittance (60-85)% with increasing in molarity in the visible region, and the evaluated energy band varied in the range of (3.5–3.3) eV with the raise of molarity. The purpose of the preparation of a thin film of indium sulfide at several rates is to get thin films with a high degree of chemical balance (Stoichometery) and a high degree of crystallization.