We use the Stillinger-Weber potential to examine the migration of a Si atom adsorbed on Si(100)-2 × 1 surface. The adsorption sites and the barriers between them are determined by energy minimization and used to estimate the rates of the site to site hopping. A stochastic kinetic simulation uses these rates to determine how the adsorbed atom migrates on the surface. We find that the mobility is highly anisotropic and that the motion is quasi one-dimensional. The particle diffuses along the dimer row and then it gets trapped on sites located between the dimers. The activation energy for the diffusion constant is a complicated function of the energy barriers separating the surface sites and the pre-exponential factor may have unusual values.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Surfaces and Interfaces
- Surfaces, Coatings and Films
- Materials Chemistry