A deep-level transient spectroscopic study was made of the conversion of the divacancy-related energy level, at Ev + 0.19eV, to a level at Ev + 0.24eV upon annealing at temperatures of between 200 and 300C. According to the literature, both levels were associated with the donor level of the di-vacancy. Diodes which were produced on p-type float-zone and Czochralski wafers, with B concentrations of 1.8 x 1014 or 2.6 x 1015/cm3, which had been irradiated with 2MeV electrons. After isothermal and isochronal annealing, the observed defects were characterized electrically. The observed conversion was suggested to involve a gradual transformation of the di-vacancy to a divacancy-O complex.

M.A.Trauwaert, J.Vanhellemont, H.E.Maes, A.M.Van Bavel, G.Langouche, A.Stesmans, P.Clauws: Materials Science Forum, 1995, 196-201, 1147-52