The migration of B in pre-amorphized material was studied as a function of the C ion implantation dose. The 20keV B ions were implanted to a dose of 1015/cm2, after implantation with 60 to 90keV C ions to give a pre-amorphized depth of 230nm. It was shown that transient enhanced diffusion occurred even in the pre-amorphized region without C+ implantation. The diffusion coefficient was larger than normal, by about one order of magnitude, during annealing at 1000C for 15s. This enhancement was eliminated by C+ implantation to a dose of about 1015/cm2. Such implantation also reduced the number of defects at the amorphous/crystal interface. It was suggested that the implanted C acted as a sink for excess interstitials.

S.Nishikawa, A.Tanaka, T.Yamaji: Applied Physics Letters, 1992, 60[18], 2270-2