An atomic-scale description was provided for the long-range O migration through the disordered SiO2 oxide during Si oxidation. First-principles calculations, classical molecular dynamics, and Monte Carlo simulations were used in sequence to span the relevant length and time scales. The O2 molecule was firmly identified as the transported O species and was found to percolate through interstices without exchanging O atoms with the network. The interstitial network for O2 diffusion was statistically described in terms of its potential energy landscape and connectivity. The associated activation energy was found in agreement with experimental values.

Oxygen Diffusion through the Disordered Oxide Network during Silicon Oxidation. A.Bongiorno, A.Pasquarello: Physical Review Letters, 2002, 88[12], 125901 (4pp)