Influence of heat treatment on the density of radiation defects in the insulator and on the semiconductor surface in metal-insulator-silicon structures

An investigation was made of the isochronous annealing of radiation defects generated during γ-photon irradiation of metal-insulator-semiconductor (MIS) structures in the presence of a bias voltage on the metal electrode. Comprehensive studies by deep level transient spectroscopy and by recording capacitance-voltage characteristics were used to show that the built-in charge at the bulk states in the insulator was annealed at 250 degree C, the fast surface states were annealed at 350 degree C, but typical radiation defects in an Si-SiO2 transition layer were annealed only at 400 degree C. The additional bulk and surface states, which appeared in the structures when a positive bias was applied to the metal electrode during irradiation, were annealed at 120 degree C and the kinetics of annealing at higher temperatures was independent of the bias polarity