EPR evidence for a positively charged vacancy-oxygen defect in silicon

A new EPR spectrum, labeled Si-I3, has been observed in electron-irradiated n-type Czochralski silicon illuminated with approximately band-gap light. The g-tensor symmetry, the g shifts from the free-electron value, and the temperature dependence of the spectrum amplitude lead to the conclusion that the spectrum originates from a positively charged vacancy-oxygen defect.