The depth distributions and species of defects were deduced from measurements of the Doppler-broadening spectra of annihilation radiation and lifetime spectra of positrons in 6H-type material which was implanted with 200keV P+ to a dose of 1015/cm2. The annealing behavior of an amorphous layer could be divided into 4 stages. Stages I (100 to 500C) and II (500 to 1100C) were attributed to the relaxation of amorphous networks and to the agglomeration of open spaces due to the rearrangement of atoms, respectively. In states III (1100 to 1500C) and IV (1500 to 1700C), which corresponded to the recrystallization of the amorphous layer, the mean size of the open volume of defects decreased with increasing annealing temperature. These defects were identified as being open spaces which were adjacent to extended defects. Vacancy-type defects were found at high concentrations in the sub-surface region (less than 100nm), even after annealing at 1700C.

Crystallization of an Amorphous Layer in P+-Implanted 6H-SiC Studied by Monoenergetic Positron Beams A.Uedono, S.Tanigawa, T.Ohshima, H.Itoh, M.Yoshikawa, I.Nashiyama, T.Frank, G.Pensl, R.Suzuki, T.Ohdaira, T.Mikado: Journal of Applied Physics, 2000, 87[9], 4119-25