Stability of HF-etched Si(100) surfaces in oxygen ambient

In situ multiple internal reflection infrared absorption spectroscopy of H-passivated silicon surfaces in controlled oxygen environments reveals that direct oxygen incorporation into the surface Si-Si bonds occurs without surface hydrogen removal, in the temperature range of 550-590 K for 1-20 mTorr O-2 pressures. The kinetics of the O-2 insertion process display overall effective activation energies of 1.6 to 1.7 eV and prefactors controlled primarily by Si-H steric hindrance for O-2 to access Si-Si backbonds. (C) 2001 American Institute of Physics.