First-principles theory was used to calculate the interactions between interstitial Fe or the Fe-B pair and a vacancy, between interstitial Fe and a divacancy, O-vacancy pair, self-interstitial, and interstitial C, as well as substitutional C, interstitial O, and the O dimer in Si. The structures, charge and spin states, binding energies, and, in some cases, vibrational spectra were predicted. The gap levels were estimated by using the marker method. The strongest interactions involved vacancies, resulted in the formation of pairs of metastable defects, and profoundly changed the electrical activity of the component species. The Fe was also trapped at self-interstitial-type defects, but not at interstitial O or substitutional C. Several observed, but incompletely characterized, defects were identified and trends in the behavior of Fe in Si were discussed.

Iron in Silicon - Interactions with Radiation Defects, Carbon and Oxygen. S.K.Estreicher, M.Sanati, N.G.Szwacki: Physical Review B, 2008, 77[12], 125214 (9pp)