Influence of Thickness on Structural and optical properties of the CdS single crystal nano structure thin films Deposited Via Thermal evapovation

Abstract

In this paper, the preparation of the harmful cadmium CdS on glass bases, prepared by thermal evaporation in the vacuum and study of optical and structural properties. The thickness and structural of the films were determined by (FESEM cross section). The results of the X-ray diffraction (XRD) showed that the films had a single crystal the hexagonal structure and the roughness and granular size were studied by using the (AFM) in two dimensions and three dimensions. The surface of the films was formed from clusters of granules called cluster and the roughness rate increased . The optical properties were studied through the (T) permeability spectrum of cadmium sulfide (CdS) prepared in wavelength range (400,650,750) nm. It was noted hat the permeability of cadmium sulfide was low and when the permeability decreased, the energy gap increased. And the value of the optical energy gap is(2.6eV) for cadmium sulfide. The optical properties were calculated as a function of the photon energy, which includes the absorption coefficient. The optical properties suggest that the prepared had a direct energy gap of 2.5,2.2,1.95eV where the energy gap was observed by increasing the thickness of the prepared the films was studied for the manufacture of electronic devices such as solar cells. The morphology of the surface was studied through (AFM) ,and the study of the optical properties of the films by UV-visible, and the CdS of the (PVD) thermal discharge were prepared in vacuum.