Study of deep centers in near-surface layers of n-type silicon irradiated by electrons

Concentration profiles of radiation-induced defects near the n-silicon surface irradiated with fast electrons are investigated. Diffusion lenght of vacancies in silicon grown by the Czochralsky method (Lsub(v)=0.5μm) was determined from the profiles of A centers. It is found that the center with the level Esub(c)=0.36 eV, formed owing to the irradiation and annealing, on irradiation is introduced to the crystal volume more effectively. This attributes to a lower effectiveness of radiation-stimulated annealing near the surface. Diffusion run off of centers with a level Esub(c)=0.39 eV (divacancies) onto the surface during thermal annealing is observed. The coefficient of thermal, divacancy diffusion is determined from the concentration profiles after annealings