Electronic conduction mechanisms and defects in polycrystalline antimony selenide

Abstract

A study on the electronic conduction mechanisms and electrically active defects in polycrystalline Sb2Se3 is presented. It is shown that, for temperatures above 200 K the electrical transport is dominated by thermal emission of free holes, ionized from shallow acceptors, over the inter-grain potential barriers. The temperature dependence of the holes mobility, limited by the inter-grain potential barriers, is the main contributor to the observed conductivity thermal activation energy. At lower temperatures, nearest-neigbour and Mott variable range hopping transport in the bulk of the grains are the dominant conduction mechanisms. Based on this study, the important parameters of the electronic structure of the Sb2Se3 thin-film such as free hole density and mobility, inter-grain potential barrier height, intergrain trap density, shallow acceptor ionization energy, acceptor density, net donor density and compensation ratio are reported.