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A model of interstitial impurity migration is proposed which explains the redistribution of ion-implanted boron in low-temperature annealing of nonamorphized silicon layers. It is supposed that nonequilibrium boron interstitials are generated either in the course of ion implantation or at the initial stage of thermal treatment and that they migrate inward and to the surface of a semiconductor in the basic stage of annealing. It is shown that the form of the “tail” in the boron profile with the logarithmic concentration axis changes from a straight line if the average lifetime of impurity interstitials is substantially shorter than the annealing duration to that bending upwards for increasing lifetime.

The calculated impurity concentration profiles are in excellent agreement with the experimental data describing the redistribution of implanted boron for low-temperature annealing at 750${}^{\circ }$C for 1h and at 800${}^{\circ }$C for 35min. Simultaneously, the experimental phenomenon of incomplete electrical activation of boron atoms in the “tail” region is naturally explained.

In this paper, we present the first work in developing a second nearest-neighbor modified embedded atom method (2NN-MEAM) potential function that can be used to model interatomic interactions in both $\alpha$ boron and $\beta$ boron polymorphs. To fit the potential parameters by optimization, some physical properties and elastic constants of boron, calculated from the density functional theory, are adopted as the targets in the objective function. The developed potential is utilized in molecular dynamics (MD) simulations to calculate the physical, mechanical, and thermal properties of $\alpha$ boron and $\beta$ boron. A comprehensive comparison is conducted between the MD simulations and various experimental studies if available to validate the developed potential function. It is concluded that the developed 2NN-MEAM potential can be practically employed in MD modeling and simulation of boron. This work will also enhance the future development of binary potentials for boron compounds to study boron-based composites via MD.