Nitrogen impurities form complexes with native defects such as vacancies and self-interstitials in Si which were stable to high temperatures. These complexes could then suppress the formation of large vacancy and self-interstitial clusters. However, there was little known about their properties. First-principles density-functional theory was used to determine the local vibrational modes, electrical levels and stability of a range of N-interstitial and vacancy complexes. Tentative assignments of the ABC photoluminescence line and the trigonal SL6 electron paramagnetic resonance center were made to substitutional-N pair and the substitutional-N–vacancy complex.

Vibrational Modes and Electronic Properties of Nitrogen Defects in Silicon. J.P.Goss, I.Hahn, R.Jones, P.R.Briddon, S.Öberg: Physical Review B, 2003, 67[4], 045206 (11pp)