Vacancy-type defects and their annealing behavior were studied, using mono-energetic positron beams, in 6H-type samples which had been implanted with 200keV P+. In specimens which had been implanted to a dose of 1013/cm2, the mean size of the open volume of defects was estimated to be close to that of divacancies. On the basis of the annealing behavior of the S-parameter for the annihilation of positrons that were trapped by vacancy-type defects, the temperature range for the annealing of vacancy-type defects was divided into 3 parts. The annealing behaviors in stages I (200 to 700C) and II (700 to 1000C) were attributed to the agglomeration of defects via the migration of monovacancies, and vacancy complexes such as divacancies, respectively. In stage II, near to the defect-free region, the agglomeration of defects was suppressed by the recombination of vacancy-type defects and interstitials. Stage III (1000 to 1300C) was attributed to the formation of extended defects, and their recovery.

A.Uedono, T.Ohshima, H.Itoh, R.Suzuki, T.Ohdaira, S.Tanigawa, Y.Aoki, M.Yoshikawa, I.Nashiyama, T.Mikado: Japanese Journal of Applied Physics - 1, 1998, 37[5A], 2422-9