Annealing temperature dependent structural and optical properties of nanocrystalline ZnTe thin films developed by electrodeposition technique

Abstract

ZnTe is a potential material for device fabrication because of the suitable optoelectronic properties. In this work, a nanocrystalline binary semiconductor zinc telluride (ZnTe) was developed in non-aqueous medium through an electrochemical deposition process. We report the structural and optical properties of developed ZnTe films deposited on nickel and glass substrate at various temperatures (350–500 °C). The solid state and optical properties of developed film was characterized by XRD, SEM, EDS, UV Vis spectroscopy and Photoluminescence spectroscopy. XRD analysis indicates the polycrystalline deposits in all the cases. The sharpness of the peak increases due to annealing of the film and average crystalline size increases. SEM photograph indicate that grains are uniform and densely distributed over the surface. The main effect of annealing temperature was helpful to improve crystalline structure, whereas the bandgap of semiconductor was reduced due to large density of dislocations. This study is vital for the optimization of the annealing temperature for growth of good-quality ZnTe films, which are necessary for device fabrication and applications.