Effect of deposition time on the band-gap and optical properties of chemical bath deposited CdNiS thin films.

Abstract

Thin films of CdNiS have been grown on glass substrate using the chemical bath deposition (CBD) technique. Cadmium chloride, Nickel chloride and thiourea were taken as the source of cadmium, cobalt and sulphur respectively. Effects of deposition time on the films’ optical properties and band gap energy were studied by depositing CdNiS thin films under different dip time. Optical properties such as absorptance and transmittance were determined using Unico UV-2102 PC Spectrophotometer, at normal incidence of light in the wavelength range of 200-1000μm. From the absorbance and transmittance spectra, the band gap energy was determined. The high transmittance of the films in certain range of the solar spectrum and the large band gap make them good material for selective coatings and absorber layer for solar cell, respectively.