Formation of Thin Oxide Films on Room-Temperature Silicon (100) by Exposure to a Neutral Beam of Hyperthermal Atomic and Molecular Oxygen

Silicon (100) surfaces at room temperature were oxidized in a hyperthermal beam containing nearly equal fractions of atomic and molecular oxygen. An oxide layer with a terminal thickness of 4.5 nm was formed on the Si surfaces, and this layer was composed mostly of silicon dioxide (SiO2). However, a significant fraction of suboxide (SiO x , x<2) was formed at the Si/SiO2 interface, where the intrinsic stress was high. Post annealing in vacuum at 1000°C for 30 min decreased the amount of suboxide and stress at the interface.