Low intensity light ions (H+ or He2+) irradiation of silicon introduced EPR Si–AA12 defect. Si–AA12 revealed close correlations with the deep-level transient spectroscopy E1=Ec−0.39eV minority trap. Impurity interstitials or self-interstitial associated secondary defects, such as interstitial carbon (Ci) or aluminium (Ali) or self-interstitial–oxygen complex (Sii–Oi), appeared upon annealing at 280 to 350K and especially under injection at 77K of Si–AA12 and E1 state. Strong 1:1 correlation between injection annealing of E1 and increasing Ci in FZ-Si and sum of (Sii–Oi)+Ci as well observed reversible transformation of Si–AA12 and E1 onto (Sii–Oi) and their re-emission after annealing (Sii–Oi) allow to attribute these states to a isolated self-interstitial. Thermally stimulated capacitance data showed negative U-properties of E1 predicted by theoretical calculations and supports this identification

Self-Interstitials and Related Defects in Irradiated Silicon. Y.V.Gorelkinskii, K.A.Abdullin, B.N.Mukashev, T.S.Turmagambetov: Physica B, 2009, 404[23-24], 4579-82