Effects of CdCl2 treatment on the properties of CdS films prepared by r.f. magnetron sputtering

Abstract Effects of the thickness of CdCl 2 layer and the annealing on structural and optical properties of sputter-deposited CdS films were investigated. The annealing process of evaporated CdCl 2 was carried out by heating the sample in air at 350–500 °C for 20 min. As the thickness of the CdCl 2 increases, the (002) peak of CdS becomes weak and the other peaks of CdS increases. Especially, for 200 nm CdCl 2 , the preferential orientation of the (002) plane disappears and the c -axis of the CdS film tends to orient parallel to the substrate. As the CdCl 2 layer is thicker, the grains are enlarged significantly. The improvement of optical properties of CdS films with thicker CdCl 2 layer might be successfully employed in achieving better conversion efficiencies in solar cells.