Influence of single atomic height steps on F₂ reactions with Si(100)-2-1 Reactions with Si(100)-2x1

We have investigated the effect of single atomic height steps on the reactivity of F₂ molecules with a clean Si(100)-2x1 reconstructed surface via molecular dynamics simulations using an ab initio derived Stillinger-Weber-type potential. Of the three types of single atomic height steps thought to commonly exist on Si(100) surfaces, the presence of the lower energy S_Aand S_Brebonded steps had a negligible effect on reactivity compared to the perfect (100) surface while the higher energy S_B’nonbonded step slightly increased the adsorption probability. These results suggest that current discrepancies between experimental observations and theoretical predictions of the partitioning between reaction channels for F₂ reacting with the Si(100) surface are not due to the presence of steps on the silicon surface in the laboratory.