The states of intrinsic point defects mediating self-diffusion were identified, and the change in predominant diffusion mechanism responsible for self-diffusion over a wide temperature range was clarified using ab initio methods. A reliable self-diffusion model was presented which suggested that vacancy and self-interstitial mechanisms predominated below and above 1220K, respectively. The calculations attributed Si self-diffusion at lower and higher temperatures to single point defects rather than extended defects. The calculations also provided valuable information on the energy levels and the thermal equilibrium concentrations of point defects.

Ab initio Study of Self-Diffusion in Silicon over a Wide Temperature Range - Point Defect States and Migration Mechanisms. S.Ma, S.Wang: Physical Review B, 2010, 81[19], 193203