An atomic-scale description is provided for the long-range oxygen migration through the disordered SiO2 oxide during silicon oxidation. First-principles calculations, classical molecular dynamics, and Monte Carlo simulations are used in sequence to span the relevant length and time scales. The O-2 molecule is firmly identified as the transported oxygen species and is found to percolate through interstices without exchanging oxygen atoms with the network. The interstitial network for O-2 diffusion is statistically described in terms of its potential energy landscape and connectivity. The associated activation energy is found in agreement with experimental values.
Enrico Amico, Antonella Romano, Emahnuel Troisi Lopez