Transport properties in Se–Te–Ge glasses

Abstract

Addition of germanium to the Se–Te alloy causes structural changes which modify the band structure and hence the electrical properties of the Se–Te alloy. In the present work, electrical, optical, and structural properties of Se–Te–Ge have been studied. The activation energies calculated from the dc resistivity measurements were changed from 0.15 to 0.39 eV with the change of germanium and thickness of the film. Refractive index n, extinction coefficient k, and dielectric constant ε of Se–Te–Ge alloy thin films showed significant change with light energy. Crystallization of the sample is achieved at 573 K. The amorphous Se–Te–Ge system is useful as a good photovoltaic material. The dc conductivity measurements were carried out from 294 to 555 K. The effect of heat treatment on optical absorption was investigated.