The O-vacancy and peroxy linkage pairs were investigated by using ab initio density functional calculations. It was found that pair defects, in which the peroxy linkage was located adjacent to the O vacancy, had an electron-trapped thermodynamic charge state level in the Si band-gap and that the geometrical structure of the electron-trapped level was the asymmetrical double Si---O---Si bond structure of the pair defect.

New Intrinsic Pair Defects in Silicon Dioxide Interface. I.Kitagawa, T.Maruizumi: Applied Surface Science, 2003, 216[1-4], 264-9