Effects of various deposition times and RF powers on CdTe thin film growth using magnetron sputtering

Cadmium telluride (CdTe) is a p-type II-VIcompound semiconductor, which is an active componentfor producing photovoltaic solar cells in the form of thinfilms, due to its desirable physical properties. In this study,CdTe film was deposited using the radio frequency (RF)magnetron sputtering system onto a glass substrate. Toimprove the properties of the CdTe film, effects of twoexperimental parameters of deposition time and RF powerwere investigated on the physical properties of the CdTefilms. X-ray Diffraction (XRD), atomic force microscopy(AFM) and spectrophotometer were used to study thestructural, morphological and optical properties of theCdTe samples grown at different experimental conditions,respectively. Our results suggest that film propertiesstrongly depend on the experimental parameters and byoptimizing these parameters, it is possible to tune thedesired structural, morphological and optical properties.From XRD data, it is found that increasing the depositiontime and RF power leads to increasing the crystallinity aswell as the crystal sizes of the grown film, and all the filmsrepresent zinc blende cubic structure. Roughness valuesgiven from AFM images suggest increasing the roughnessof the CdTe films by increasing the RF power and depositiontimes. Finally, optical investigations reveal increasingthe film band gaps by increasing the RF power and thedeposition time.