Deep States in a-Si:H - Changes with Doping and Applied Stress.

Abstract

AbstractRecent Constant Photocurrent Method (CPM) results and a new model of a-Si:H density of states are briefly reviewed. The small but systematic changes of subgap absorption (α) with the applied external stress have been found. When light-soaking is done under the applied stress the strong increase of α is observed. The μτ (mobility-lifetime) versus α duality is demonstrated. The increase of the dangling bond density, combined with the change of its charge state, is used for the explanation of duality. The light induced creation of dangling bond-impurity intimate pairs is speculated to be the driving force for the Fermi level shift.