Classical-trajectory calculations onAr+sputtering of a Si(001) surface using anabinitiopotential

We describe classical-trajectory calculations of sputtering yields for ${\mathrm{Ar}}^{+}$-ion collisions with a Si(001) surface. The ${\mathrm{Ar}}^{+}$-Si and short-ranged Si-Si interaction potentials were calculated using the ab initio Hartree-Fock and configuration-interaction methods. The low-energy potential describing the silicon solid is the two- and three-body form due to Stillinger and Weber. We compare the calculated sputtering yields with experiment. The potential-energy surface strongly influences the calculated sputtering yields, and it is found that the most reasonable agreement is obtained from our potentials using the (2×1) Si(001) reconstructed surface rather than the bulk-terminated surface. Analysis of the kinetic energy and angular distributions of the sputtered silicon atoms and of cluster yields has provided a mechanism of ejection.