The Solid-State characteristics of ZnS thin films grown by CBD technique

ZnS thin films were coated onto fluorine doped tin oxide glass substrates using chemical bath deposition technique. The bath solution was made from 0.1 M of zinc nitrate and thiourea as the source of zinc and sulphur ions, respectively. The precursor solution temperature was kept at 70oC and the time of deposition was varied between 5 and 30 min. The impact of time of deposition was then examined on some solid state characteristics of the films. The structural properties such as crystallite size, micro lattice strain and dislocation density were examined using x-ray diffractometer. The morphological and compositional features were studied using scanning electron microscopic and energy dispersive spectroscopic. The optical characteristics were measured with Uv vis spectrophotometry. The investigation showed that some films were amorphous and some had polycrystalline structure, the films were rough, dense and covered the substrates, the compositional analysis confirmed the presence of zinc, sulphur and oxygen. The optical analysis showed that the films had high bandgap between 3.79 and 3.97 eV.