Oxidation of the 8 × 8-reconstructed β-Si3N4(0 0 0 1) surface: A photoemission study

The thermal oxidation of the β-Si3N4(0 0 0 1)-8 × 8 surface has been carried out. The spectroscopic characterization has been performed by high resolution core-level and by angle-resolved photoemission spectroscopy. Our findings demonstrate that the surface shows a low but clear reactivity with oxygen. The known resonance ascribed to the 8 × 8 reconstruction results strongly affected by the oxygen dosing, demonstrating the involvement of the topmost nitride atoms.