Diffusion of point defects near stacking faults in 3C-SiC via first-principles calculations

Abstract

First-principles calculations are used to investigate diffusion of point defects near stacking faults in 3C-SiC and to identify the migration mechanisms. Compared with the energy barriers for defects in the bulk, the migration barriers for both Si and C vacancies and Si interstitials near the stacking fault are found to decrease. For C interstitials, the energy barriers increase depending on the electronic localization in the stacking fault region. The lower barriers for Si interstitial diffusion near the faults may be responsible for the enhanced defect annihilation observed under irradiation in 3C-SiC with high densities of stacking faults.