The atomic scale oxidation of the alpha -SiC(0001)-(3 x 3) surface is inves
tigated by atom-resolved scanning tunneling microscopy, core level synchrot
ron radiation based photoemission spectroscopy, and infrared absorption spe
ctroscopy. The results reveal that the initial oxidation takes place throug
h the relaxation of lower layers, away from the surface dangling bond, in s
harp contrast to silicon oxidation.