Optical band gap studies on Zn-Te pellets

Abstract

Spectroscopic techniques are very useful for characterizing semiconducting and conducting materials. The optical properties (specially reflection spectra) of Zn_xTe_100-x(<i style="">x</i>=5, 10, 30 and 50) material in pellet form were studied. Polycrystalline semiconducting material has been prepared by Melt quenching method by taking pure Zn and pure Se in appropriate atomic weight ratio. The polycrystalline nature of Zn₅Te₉₅ was confirmed by XRD studies. In order to compare the studies on so prepared polycrystalline material and commercially obtained pure Zn₅₀Te₅₀ material, investigations were carried out on both types of samples. From the analysis of reflection spectra, energy band gaps of Zn_xTe_100-x material have been determined, which were found to increase from 1.67 to 2.31 eV. It is observed that the optical band gap of laboratory prepared Zn₅₀Te₅₀ material is in excellent agreement with that of commercially obtained pure Zn₅₀Te₅₀ material.