MONTE-CARLO SIMULATIONS OF GROWTH OF SB ATOMS ON THE GAAS(110) SURFACE

A Monte Carlo computer-simulation study of the growth of submonolayer coverages of Sb atoms on the GaAs(110) surface is reported. The Monte Carlo model incorporates explicitly the substrate-overlayer tetrahedral lattice structure and considers atom-atom interactions out to second-nearest-neighbor distances. The surface configuration-dependent dissociative chemisorption of molecular Sb is also included in the model. Atom-atom interaction energies employed in the simulation of diffusion events are obtained from the application of an empirical tight-binding total-energy calculational procedure to selected atom configurations, providing an internally consistent set of energy parameters. Simulated growth as a function of temperature in the range 300-500 K is discussed in detail for simulation parameters corresponding to typical experimental growth conditions. Details of the simulated growth may be understood by a consideration of the diffusion activation barriers involved at different stages of the growth. The model predicts a predominance of odd- over even-numbered-atom Sb chains at submonolayer coverages. Changes in the interface resulting from subsequent annealing after deposition of submonolayer Sb coverages are also briefly discussed. © 1994 The American Physical Society.