Atomic-Scale Simulation of Silicon Atomic Beam Deposition

Abstract

ABSTRACTThe mechanisms which control low energy (10–100 eV) beam deposition of silicon onto a relaxed (111) silicon substrate have been studied using a molecular dynamics technique. A many-body empirical potential was used to describe the covalent Si-Si bonding. 10 eV silicon beams with near-perpendicular incidence were simulated to study capture mechanisms and the local lattice excitation resulting from impact. Grazing angles of incidence (3°–30°) were studied for beam energies of 20–100 eV. For incidence angles less than an energy- and orientation-dependent critical value, the phenomenon of ‘surface channeling’ is predicted, in which the incoming particle is steered parallel to, and roughly 2 Å above, the surface of the substrate through inelastic substrate interactions. The phenomena seen in low-energy beam deposition offer new avenues of control over growth of modulated semiconductor structures.