The migration of monovacancies (V0) and self-interstitials (I) was observed in ion-implanted low-doped float-zone Si by variable-energy positron annihilation spectroscopy. V0 and I were created by the in situ implantation of ~20keV He ions below 50K. Monitoring the time evolution of the vacancy response during isothermal heating enabled the measurement of activation energies for V0 and I migration of 0.078(7) and 0.46(28)eV, respectively. In highly As-doped Si, partial V annihilation occurred via free I migration, with a second stage of annealing, probably associated with V-As complexes, above room temperature.

Monovacancy and Interstitial Migration in Ion-Implanted Silicon. P.G.Coleman, C.P.Burrows: Physical Review Letters, 2007, 98[26], 265502