Incomplete melting of the Si(100) surface from molecular-dynamics simulations using the Effective-Medium Tight-Binding model

摘要

We present molecular-dynamics simulations of the Si(100) surface in thetemperature range 1100-1750K. To describe the total energy and forces we usethe Effective-Medium Tight-Binding model. The defect-free surface is found tomelt at the bulk melting point, which we determine to be 1650 K, but for asurface with dimer vacancies we find a pre-melting of the first two layers 100K below the melting point. We show that these findings can rationalize recentexperimental studies of the high temperature Si(100) surface.