Molecular dynamics study of diffusion barriers of Si and C adatoms on Si surfaces

Abstract

Diffusion of Si and C adatoms on Si surface play very important role in the process of SiC film formation by Molecular Beam Epitaxy with deposition of carbon atoms on silicon substrate. Nowadays the reliable measurements of surface diffusion and initial stages of nanofilm growth on the Si substrates are rare. Theoretical studies in frames of various ab initio techniques are restricted and cover only limited set of simple phenomena like single adatom absorption and diffusion on perfect surfaces. In the present work we used atomic scale modeling in frame of classical molecular dynamics (MD) method in order to calculate diffusion barriers of Si and C adatoms on Si(100) 2x1 reconstructed and Si(111) surfaces. Tersoff potential was used in the MD code for interatomic interactions description in the Si-C system. Diffusion barriers were studied by means of Potential Energy Surface calculation for Si and C adatoms. Calculated diffusion barriers values were compared with available experimental data and data of ab initio simulations.