Accurate modeling of ultra-low energy ion implantation is becoming increasingly more important as MOS devices shrink to deep submicron dimensions, and the required junction depths become shallower than 50 nm. To this end, an efficient Monte Carlo ion implantation model based on a substantially modified Binary Collision Approximation (BCA) has been developed and implemented in UT-MARLOWE. The model eliminates the asymptotic path approximation and explicitly includes 3-body interactions, allowing for accurate modeling of ultra-low energy collisions. In this paper, we report on the experimental verification of the model, as well as refinements and corrections subsequently introduced. This paper also discusses the difficulties in obtaining accurate SIMS profiles for ultra-shallow implants, and methods for overcoming them. Surface effects are also discussed, and their impact on the dose-dependence of the profiles is examined. The model has been verified for arsenic and boron, for energies down to 1 keV and 500 eV, respectively. This new model is found to be in good agreement with the experimental data.
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