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 implanta tion 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, wh ich increases with increasing the vacancy supersaturation generated in the Sb-doped region by the knock-on recoil mechanism. TED lasts a few minutes f or annealing at 800 and 900 degrees C. The results indicate that at these t emperatures the buildup and decay of vacancy supersaturation in the near-su rface region occurs on a shorter time scale than the release of interstitia ls from the buried damage layer. The dominant role of vacancies is also ind icated by the very low TED observed in B-doped samples processed under simi lar conditions. For 1000 degrees C annealing some effect of the retardation induced on Sb diffusion by interstitials flowing from the deep region is f ound after 15 min annealing. Preliminary results of defect injection by non amorphizing medium-energy implants indicate that a smaller, yet nonvanishin g, effect of Sb TED persists even under conditions where B diffusivity is s trongly enhanced. (C) 2000 American Institute of Physics. [S0021-8979(00)03 412-5].