Effects of Al content on physical properties of ZnS thin films prepared by chemical bath deposition

Abstract

In this work we report the effect of aluminum on the physical properties of Al-doped ZnS thin films. Our samples have been synthesized by chemical bath deposition from aqueous solutions (Sahraei and Darafarin in Spectrochim Acta A Mol Biomol Spectrosc 149:941–948, 2015). X-ray diffraction analysis revealed that the films are monocrystalline and showed (111) preferred orientation for all the doping concentration. Doping ZnS thin films shows significant changes in the transmittance characteristics in the visible range. The refractive index dispersion and extinction coefficients are adequately described by the Wemple–DiDomenico model. The value of oscillator energy E0, dispersion energy Ed, the high-frequency dielectric constant ɛ∞ and ratio of the carrier concentration to the effective mass N/m* were estimated according to the models of Wemple–DiDomenico and Spitzer–Fan. Photoluminescence behavior of Al-doped ZnS thin films was also studied.