The diffusivity of B was enhanced by pressure, as characterized by an activation volume equal to -0.17 times the atomic volume. This volume was close to the formation volume of the self-interstitial, as predicted by atomistic calculations. The results for a hydrostatic pressure were used to make predictions of the effect of biaxial strain upon diffusion. By assuming an interstitial-based mechanism and a range of values for the anisotropy in the migration volume, these results were compared with atomistic calculations, and with the measured dependence of B diffusion upon biaxial strain. Qualitative agreement was found between an interstitial-based mechanism and the measured strain effect upon diffusion in Si-Ge alloys. This was not true of strain effects measured in pure Si.

Activation Volume for Boron Diffusion in Silicon. Y.Zhao, M.J.Aziz, H.J.Gossmann, S.Mitha, D.Schiferl: Applied Physics Letters, 1999, 74[1], 31-3