The nitrogen-pair oxygen defect in silicon

The nitrogen-pair oxygen defect in silicon has been studied by infrared absorption spectroscopy on samples implanted with various combinations of ¹⁴N, ¹⁵N, ¹⁶O and ¹⁷O. The measurements give direct evidence for the involvement of nitrogen and oxygen in the defect and show that the impurity atoms comprising the defect are only weakly coupled. Ab initio cluster calculation on several models of the nitrogen-pair oxygen defect have been performed and are compared with experiment. Based on these investigations a model consisting of a bridging oxygen atom adjacent to the nitrogen pair is suggested.