Structurally tailored Cu(InxGa1 − x) Se2 thin films via RF magnetron sputtering

Cu(InxGa1 − x) Se2 (CIGS) thin films were deposited onto soda-lime glass substrates with Mo coating via the one step radio frequency (RF) magnetron sputtering without a post-selenization process at the substrate temperature varying from 550 °C to 630 °C. The effect of deposition temperature on the structural properties of CIGS thin films has been characterized by X-ray diffraction (XRD), Raman spectroscopy, field emission scanning electron microscopy (FESEM), and energy dispersive X-ray spectroscopy (EDX). It was found that an increased deposition temperature of up to 580 °C contributes to produce the smooth surface, large grain size, and increased crystallinity of the thin films. But further increased deposition temperature results in a decrease in smoothness and an increase in grain size. The optimized temperature (580 °C) shows the best effect on the composition and formation of the chalcopyrite structure without impurities.