Molecular beam epitaxial growth of Si(001): A Monte Carlo study

The results of a Monte Carlo (MC) simulation study of epitaxial growth dynamics of Si(001) over a wide range of deposition rates (0.001-100 monolayers/s) and substrate temperatures (500-1000 K) are reported. The MC model, which allows the formation of bulk vacancies and overhangs in the tetrahedral coordination of silicon, is proposed. Surface relaxation (dimerization) and atom-atom interactions extending as far out as second-neighbour sites are included in the model. Our results demonstrate that the effect of the formation of vacant sites is pronounced only at low temperatures, where there is no active hopping of atoms, while at high temperatures this effect is washed out by intensive hopping of atoms.