Study of dielectric properties of some bulk Cu-As-Se-I chalcogenides

Abstract

© 2018, National Institute R and D of Materials Physics. All rights reserved. The impedance spectroscopy technique was used to study the frequency dependence of some dielectric parameters in the frequency range from 100 Hz to 1 MHz for the bulk amorphous semiconducting glasses from the system Cux[(As2Se3)0.9(AsI3)0.1]100−x (x=0, 1, 5, 10 and 15 at. % Cu). The measurements were carried out at different temperatures (298–398 K). Values of the real and imaginary part of dielectric permittivity (ε′ and ε″) were found to decrease with frequency and increase with temperature. The obtained results are interpreted in terms of the Debye theory of molecular dipoles. They indicated the existence of different types of dipoles that determine the mechanism of dielectric behavior for the investigated compounds. The parameters of dielectric permittivity are explained according to a model of hopping over the potential barrier between the localized sites. The maximum barrier height WM was calculated from the dielectric measurements in accordance with Giuntini equation.