Investigation of annealing temperature effect on magnetron sputtered cadmium sulfide thin film properties

Cadmium sulfide (CdS) thin films are depositedon the fluorine doped tin oxide coated glass substrate usingthe radio frequency magnetron sputtering setup. The effectsof annealing in air on the structural, morphological, andoptical properties of CdS thin film are studied. Optimalannealing temperature is investigated by annealing the CdSthin film at different annealing temperatures of 300, 400,and 500 ̊ C. Thin films of CdS are characterized by X-raydiffractometer analysis, field emission scanning electronmicroscopy, atomic force microscopy, UV–Vis–NIRspectrophotometer and four point probe. The as-grown CdSfilms are found to be polycrystalline in nature with amixture of cubic and hexagonal phases. By increasing theannealing temperature to 500 ̊ C, CdS film showed cubicphase, indicating the phase transition of CdS. It is foundfrom physical characterizations that the heat treatment inair increased the mean grain size, the transmission, and thesurface roughness of the CdS thin film, which are desired tothe application in solar cells as a window layer material.