A model for Fermi-level pinning in semiconductors: radiation defects, interface boundaries

Abstract

This paper reports the new theoretical model of a defective state with the most localized wave function, which corresponds to the deepest energy level E B within the energetic interval near the forbidden gap of each semiconductor. A special characteristic of this localized state is established in the phenomenon of the Fermi-level pinning in semiconductors. This deepest energy level plays the fundamental role similar to the electronic chemical potential in the bulk defective semiconductor and at the interface. The numerical calculations of E B-values in the IV and III–V group semiconductors are in conformity with experimental data on the Fermi-level position in the irradiated semiconductors and at the interface boundaries. The present model explains the correlation between different approaches to the problem of the Fermi-level pinning in semiconductors based on the one-particle Green function properties.