In-Depth Profiling of Suboxide Compositions in the SiO2/Si Interface by Angle Resolved X-ray Photoelectron Spectroscopy

A clean silicon surface was oxidized in a UHV chamber and in-depth profiling of suboxide compositions was carried out by using angle-resolved X-ray photoelectron spectroscopy. The existence of Si-H bonds near the oxide surface is implied because the background hydrogen in the UHV chamber reacts with the oxide surface. This hydrogenated Si bond looks like Si3+ in the Si2p spectrum. It is also shown that the SiO2/Si interface is atomically abrupt.