Implantation species dependence of transient enhanced diffusion in silicon

Abstract

The dependence of transient enhanced diffusion (TED) on implantation species has been investigated by the simulation of TED induced by P, As, and Si implantation using a unified set of parameters. The TED enhancement at short annealing times critically depends on the effective diffusivities of implanted species. Fast P diffusion induces a self-interstitial supersaturation with respect to the pseudo-equilibrium concentration, which further enhances TED. Therefore, TED induced by P implantation is faster than that by As and Si, where self-interstitials are in thermal equilibrium. At longer annealing times, the enhancement is primarily governed by self-interstitial diffusion, which depends on the carrier concentration and the implanted range, or the proximity of the damage to the surface, and faster self-interstitial diffusion leads to smaller enhancement. Furthermore, the carrier concentration, which also affects the dopant effective diffusivities and the duration of TED, varies with dose and annealing time. Therefore, the dependence on implantation species is closely related to the variations of dose, energy, and annealing time, which leads to complex TED characteristics.