Electron paramagnetic resonance and optical studies were made of the vacancies and interstitials produced in type-IIa material which was irradiated with 2MeV electrons between 90 and 900K. Post-irradiation annealing at up to 1900K was also performed. Data were presented which revealed the recombination-enhanced diffusion of self-interstitial atoms, and an analysis of the phenomenon led to the conclusion that a highly mobile interstitial, I* (perhaps a charged/neutral Td interstitial), was produced by electronic excitation and/or charge transfer. It was estimated that the migration energy for I* was 0.3eV. No evidence of vacancy recombination-enhanced diffusion was observed. The experimental data confirmed that there was a significant barrier to vacancy–interstitial recombination in diamond.

Recombination-Enhanced Diffusion of Self-Interstitial Atoms and Vacancy–Interstitial Recombination in Diamond. M.E.Newton, B.A.Campbell, D.J.Twitchen, J.M.Baker, T.R.Anthony: Diamond and Related Materials, 2002, 11[3-6], 618-22