An extensive analysis was made of the correlation factors for interstitial-mediated self-diffusion via various possible mechanisms and hopping networks in the diamond lattice using the kinetic lattice Monte Carlo approach. The correlation factor for the kick-out mechanism in the tetrahedral hopping network was calculated to be 0.73, in agreement with previous results; and the value for the hexagonal hopping network was 0.47 for the dominant mechanism. For the mechanism where a split interstitial was stable ("stable-split" mechanism), the correlation factor for the tetrahedral network stays the same while that for the hexagonal network increased to 0.62. Simulations of the diffusion of silicon involving multiple mechanisms were then performed. The choice of mechanisms was justified by ab initio calculations. It was concluded that, unlike vacancy diffusion, interstitial self-diffusion had a temperature-dependent correlation factor. This conclusion held in general for diffusion processes involving multiple mechanisms having differing activation energies. The correlation factor obtained from ab initio results for interstitial-mediated self-diffusion in silicon at 1000 to 1100C was 0.64 to 0.80, compared to the value of 0.6 extracted from experiments.

Correlation Factors for Interstitial-Mediated Self-Diffusion in the Diamond Lattice: Kinetic Lattice Monte Carlo Approach. R.Chen, S.T.Dunham: Physical Review B, 2011, 83[13], 134124