Vacancy-type defects in O+-implanted or N2+-implanted 6H-type material were studied by using a mono-energetic positron beam. In the case of specimens which had been implanted to a dose of 1013/cm2, the mean size of the open-volume defects was estimated to be close to that of divacancies. The annealing-out of the damage was found to involve the agglomeration of vacancy-type defects via the migration of C vacancies (100 to 400C), Si vacancies (400 to 800C) or vacancy complexes such as divacancies (800 to 1000C). Another process was the annealing out of open volume adjacent to extended defects (1000 to 1400C). By comparing the annealing behaviours of defects in O+-implanted and N2+-implanted specimens, the migration and agglomeration of vacancy-type defects were found to be suppressed in the former specimens. This was attributed to the formation of complexes between vacancy-type defects and O.

Oxygen-Related Defects in O+-Implanted 6H-SiC Studied by a Monoenergetic Positron Beam A.Uedono, S.Tanigawa, T.Ohshima, H.Itoh, Y.Aoki, M.Yoshikawa, I.Nashiyama: Journal of Applied Physics, 1999, 86[10], 5392-8