A kinetic Monte Carlo study of the growth of Si on Si(100) at varying angles of incident deposition

Abstract

Two- and three-dimensional kinetic Monte Carlo simulations were used to model the deposition of a hyperthermal molecular beam at varying angles of incidence. The simulations incorporate realistic deposition and diffusional moves, and feature many-layer growth for large systems containing up to 80 000 atoms. Kinetic Monte Carlo simulations for the three-dimensional model mimic the deposition and growth of Si on a Si(100) substrate at close to experimental length- and timescales. At high angles of incidence for the beam, the formation of porous columnar structures seen in the two-dimensional simulations evolve into flakes in the three-dimensional model. The growth angles of the columns and flakes follow the same general trends as previous ballistic deposition and molecular dynamics simulations, but existing theories do not adequately represent the simulation data. In the two-dimensional model, the effect of an additional step-edge reflection barrier increases the porosity of the deposited films at conditions for which columnar growth would be observed in the absence of the additional barrier. Raising the substrate temperature increases the widths of the columns and flakes perpendicular to the path of the beam. Increased substrate temperature also affects the depth to which grown films remain defect-free before columnar growth begins.