Vacancy effects in transient diffusion of Sb induced by ion implantation of Si+ and As+ ions

The influence of defects injected by room temperature, high-energy implantation of Si and As ions on the diffusion of Sb marker in Si is investigated. MeV ions induce transient enhanced diffusion (TED) of ion implanted Sb, which increases with increasing the vacancy supersaturation generated in the Sb-doped region by the knock-on recoil mechanism. TED lasts a few minutes for annealing at 800 and 900 degrees C. The results indicate that at these temperatures the buildup and decay of vacancy supersaturation in the near-surface region occurs on a shorter time scale than the release of interstitials from the buried damage layer. The dominant role of vacancies is also indicated by the very low TED observed in B-doped samples processed under similar conditions. For 1000 degrees C annealing some effect of the retardation induced on Sb diffusion by interstitials flowing from the deep region is found after 15 min annealing. Preliminary results of defect injection by nonamorphizing medium-energy implants indicate that a smaller, yet nonvanishing, effect of Sb TED persists even under conditions where B diffusivity is strongly enhanced. (C) 2000 American Institute of Physics. [S0021-8979(00)03412-5].