Comparison between Si(100) and Si(111) in the reaction with oxygen at high temperatures

In this Letter, both the dynamics and kinetics of the reaction of oxygen molecules on Si(100)p2 × 1 and Si(111)7 × 7 and 1× 1 surfaces are compared. In all three cases, two distinct adsorption channels were observed. For oxygen molecules with translational energies less than 0.08 eV, the initial sticking is not sensitive to the energy or the angle of incidence, but displays a high sensitivity to the surface structure. At higher energies, a second channel becomes effective. The initial sticking coefficient increases rapidly and scales with the normal component of the translational energy, but the dependence on surface structure is greatly diminished. The kinetics of SiO formation are qualitatively similar on all surfaces with slightly higher rates on Si(111). © 1991.