In the same way that gases react with surfaces from above, solid-state point defects such as interstitial atoms could react from below. Little attention was paid to this form of surface chemistry. Recent bulk self-diffusion measurements near the Si(100) surface had quantified Si interstitial annihilation rates, and shown that these rates could be described by an annihilation probability that varied by two orders of magnitude in response to saturation of surface dangling bonds by sub-monolayer gas adsorption. The present work showed by modelling that the interstitial annihilation kinetics were well described by a precursor mechanism in which interstitials move substantial distances parallel to the surface before incorporation.

Precursor Mechanism for Interaction of Bulk Interstitial Atoms with Si(100). X.Zhang, M.Yu, C.T.M.Kwok, R.Vaidyanathan, R.D.Braatz, E.G.Seebauer: Physical Review B, 2006, 74[23], 235301 (7pp)