Steering effects on growth instability during step-flow growth of Cu on Cu(1,1,17)

A kinetic Monte Carlo simulation in conjunction with a molecular dynamics simulation is utilized to study the effect of the steered deposition on the growth of Cu on Cu(1, 1, 17). It is found that the deposition flux becomes inhomogeneous in the step train direction and that the inhomogeneity depends on the deposition angle when the deposition is made along that direction. The steering effect is found to always increase the growth instability with respect to the case of homogeneous deposition. Further, the growth instability depends on the deposition angle and direction, showing a minimum at a certain deposition angle off-normal to the (001) terrace, and shows a strong correlation with the inhomogeneous deposition flux. The increase of the growth instability is ascribed to the strengthened step Ehrlich-Schwoebel barrier effects, which are caused by the enhanced deposition flux near the descending step edge due to the steering effect.