The diffusion of B was studied, as a function of the position of the Fermi level in the crystalline material, by using ab initio calculations. On the basis of the results, a new mechanism for B diffusion, as mediated by Si self-interstitials, was proposed. Rather than assuming the kick out of B into a mobile channel, a direct diffusion mechanism was found for the B-interstitial pair for all Fermi-level positions. The predicted activation energy of 3.5 to 3.8eV, migration barrier of 0.4 to 0.7eV and diffusion-length exponent of -0.6 to -0.2eV, were in excellent agreement with experiment.

First-Principles Study of Boron Diffusion in Silicon. W.Windl, M.M.Bunea, R.Stumpf, S.T.Dunham, M.P.Masquelier: Physical Review Letters, 1999, 83[21], 4345-8