A study was made of the diffusion of self-interstitials by means of ab initio simulations. From the results for seven temperatures between 700 and 1200C, the diffusion coefficient and the tracer correlation factor were calculated for self-diffusion as a function of temperature. By fitting an Arrhenius relationship, the migration energy and the pre-factor were calculated. A method was also presented for extracting comprehensive quantitative information concerning defect configurations and migration mechanisms from molecular dynamics simulations.
Ab initio Molecular Dynamics Simulation of Self-Interstitial Diffusion in Silicon. Sahli, B., Fichtner, W.: Physical Review B, 2005, 72[24], 245210
Table 29
Diffusivity of self-interstitials and vacancies in Si
Temperature (K) | Defect | Method | D (cm2/s) |
1500 | self-interstitial | LDA | 7.30 x 10−7 |
1250 | self-interstitial | LDA | 5.98 x 10−7 |
1100 | self-interstitial | LDA | 3.20 x 10−7 |
1000 | self-interstitial | GGA | 1.33 x 10−7 |
1500 | self-interstitial | GGA | 5.91 x 10−7 |
1250 | self-interstitial | GGA | 5.11 x 10−7 |
1100 | self-interstitial | GGA | 1.52 x 10−7 |
1000 | vacancy | LDA | 9.52 x 10−8 |
1600 | vacancy | LDA | 4.24 x 10−6 |
1400 | vacancy | LDA | 1.93 x 10−7 |
1200 | vacancy | LDA | 2.92 x 10−7 |