Defect formation in SiO₂/Si(100) by metal diffusion and reaction

Abstract

The decomposition of SiO2 films on Si(100) during ultrahigh vacuum anneal is found to be strongly enhanced by monolayer amounts of impurities deposited on the SiO2 surface. s- and p-band elements initiate decomposition via formation of volatile suboxides by surface reaction, whereas most transition metals decompose the oxide via laterally inhomogeneous growth of voids in the oxide. Transition metals need to diffuse to the SiO 2/Si interface to enhance oxide decomposition via formation of volatile SiO. It is inferred that transition metal particles should be efficient in creating electrical defects in gate oxide layers.