An improved model for boron diffusion and activation in silicon

Technologies such as solid-phase epitaxial regrowth and millisecond annealing techniques have led to a wide range of maximum temperatures and heating rates for activating dopants and eliminating ion implantation damage for transistor junction formation. Developing suitable annealing strategies depends on mathematical models that incorporate accurate defect physics. The present work describes a model that includes a newly discovered representation of defect annihilation at surfaces and of near-surface band bending, together with an improved representation of interstitial clustering. Key parameters are determined by maximum likelihood (ML) estimation and maximum a posteriori (MAP) estimation. The model yields a substantially improved ability to model the behavior of implanted boron over a wide range of annealing conditions.