The kinetics of point defect generation in this system were studied by means of electron spin resonance and infra-red absorption spectroscopic techniques. It was shown that the effects of oxidation treatments could be explained by point defect generation, and that the structural properties could be improved by suitably choosing the oxidation conditions.

D.Kropman, S.Dolgov, T.Kärner: Applied Physics A, 1996, 62[5], 469-72