IDENTIFICATION OF THE DOMINANT NITROGEN DEFECT IN SILICON

The structure of the dominant N pair defect in Si is determined from channeling, infrared local vibrational mode spectroscopy, and ab initio local density functional theory. Channeling experiments show that the N atoms are displaced by 1.1+/-0.1 angstrom from lattice sites along [100]. Annealing experiments reveal that this N site is associated with two N-related local vibrational modes originating from the N pair. The ab initio calculations demonstrate that the pair consists of two neighboring [100] oriented N-Si split interstitials, arranged in an antiparallel configuration, and with four N-Si bonds forming a square lying on {011}.