Modeling high concentration boron diffusion with dynamic clustering: Influence of the initial conditions

Boron diffusion and activation at high concentrations are key problems in the formation of shallow P+ junctions. Therefore, it is needed to understand and to predict accuratly the dopant behaviour under these conditions. In this paper, the modeling of boron is discussed, by the use of a non-equilibrium point-defect model, including amorphization and a dynamic clustering component. The initial conditions are of major importance not only for the transient enhanced diffusion, but also for the amount of active dopant. As a result, it is possible to obtain activation levels greater than the solubility limit, as observed experimentally. 1. The point-defect diffusion model A non-equilibrium point defect-model has been used throughout the study. It solves rigor-ously the interactions between dopants and point-defects (including charged species) and takes into account the ion implantation damage. Five coupled equations are needed to solve the diffusion of boron: substitutional boron Bs, interstitial boron Bi, interstitial I