Point defect-based modeling of diffusion and electrical activation of ion implanted boron in crystalline silicon

The time evolution of the transient enhanced diffusion and of the electrical activation of boron in crystalline silicon during thermal annealing subsequent to boron ion implantation is modeled by a system of diffusion-reaction equation for the dopant species and the silicon point defects. The concept of point defect impurity pair diffusion under equilibrium conditions is used to describe the diffusion process. Outdiffusion of implantation-induced silicon self-interstitials and the kick-out reaction are assumed to be the leading mechanisms for boron activation. The computed boron depth profiles are compared to data from the literature. Implantation doses from 2E14 1/cm² up to 5E15 1/cm² are analyzed, annealing temperatures and times are considered over the ranges 800 - 1000øC and 10s - 8h, respectively.