It has been recently observed that ion implantation simulators based on the binary collision approximation (BCA) are not as accurate for low energy implants (less than 5 keV), despite their success at higher energies. The accuracy of molecular dynamics based simulators on the other hand, is independent of the implantation energy, but the computation times are extremely long. This work presents a low energy ion implantation model designed to bridge the gap between the rigorous but slow molecular-dynamics ion implantation simulators, and the less rigorous but computationally efficient binary collision approximation simulators, such as UT-MARLOWE. The deficiencies of the BCA at low energies are identified, and methods of overcoming them are discussed. The asymptotic collision approximation is abandoned in favor of a more rigorous calculation, and an improved multi-body collision algorithm that makes use of approximate multi-body potentials is introduced. The model is designed with computational efficiency in mind, and is in fact faster than conventional BCA simulators. The predictions of the low-energy model are found to be in very good agreement with molecular dynamics data, and a significant improvement over BCA predictions is observed. Finally, future improvements to the model are discussed.
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