Atomic and ionic processes of silicon oxidation

Our state-of-the-art calculations for ionic and neutral oxygen species, both molecular and atomic, in amorphous silicon dioxide show the amorphous nature of the oxide changes significantly the energetics of defect processes like charge state change, incorporation into the oxide network, and splitup of the molecule. These changes imply a new picture of silicon oxidation in the ultrathin film regime that explains anomalies like layer-by-layer growth at terraces, roughness oscillations, the distribution of oxygen isotope incorporation, the effects of excitation, and deviations from Deal-Grove kinetics. Our results suggest possible alternative routes to improve oxide quality.