Compositional dependence of the physical properties of Ge 1Se 9− xTe x amorphous system

Abstract

The compositional dependence of electrical conductivity, optical absorption and refractive index of thin films of the Ge 1Se 9− x Te x amorphous system in the range 0 ≤ x ≤ 4 is investigated. The obtained results were correlated with the character of the chemical bond for the prepared compositions through a study of parameters such as average heat of atomization and average coordination number. The activation energy for electrical conduction decreases with Te content and consequently there is an increase in DC conductivity with Te content. A shift in the absorption edge towards the lower energy side of spectrum was observed due to the increase of Te content and a consequent decrease in the optical energy gap. The effect of γ-radiation up to a dose of 10 Mrad on the optical and electrical properties was also studied.