Vacancy-type defects and their annealing properties in O+- or N+-implanted 6H-type material were studied by using a mono-energetic positron beam. In 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 the size of divacancies. The annealing processes which occurred included the agglomeration of vacancy-type defects due to the migration of C vacancies (100 to 400C), Si vacancies (400 to 800C) and vacancy complexes such as divacancies (800 to 1000C), plus the annealing out of open spaces adjacent to extended defects (1000 to 1400C). By comparing the annealing behaviours of defects in O+- and N+-implanted specimens, the migration and agglomeration of vacancy-type defects were found to be suppressed in the O+-implanted specimens. This was attributed to the formation of complexes between vacancy-type defects and O. The annealing behavior of amorphous regions was also studied in specimens which had been implanted to a dose of 1015/cm2.

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