Structural and Optical properties of Cd SeGe amorphous films

Abstract

Thin films of Cd10Se75Ge15 were prepared by the conventional thermal evaporation technique on glass substrate. The chemical
composition of the films has been checked using energy dispersive X-ray spectroscopy (EDX). X-ray diffraction (XRD)
measurements have shown that all investigated compositions in powder and thin film form have amorphous nature.
Transmittance measurements in the wavelength range (350-2500nm) were used to calculate the refractive index n and the
absorption index k using Swanepole’s method. The analysis of the optical absorption data revealed that the optical band gap Eg
was indirect transitions. The optical dispersion parameters Eo and
Ed
were determined according to Wemple and Didomenico

method. The optical constants such as optical band gap
opt Eg
, complex dielectric constant and dissipation factor
tan
were

determined.