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

TL;DR

This study uses simulations to show that steering effects during Cu deposition cause inhomogeneous flux, increasing growth instability, with the effect depending on deposition angle and direction, linked to step barrier effects.

Contribution

It demonstrates how steering effects influence growth instability during Cu step-flow growth, highlighting the dependence on deposition angle and flux inhomogeneity.

Findings

Steering effects increase growth instability in Cu deposition.

Inhomogeneous flux depends on deposition angle and direction.

Growth instability correlates with enhanced step barrier effects.

Abstract

Kinetic Monte Carlo simulation in conjunction with 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 step train direction and the inhomogeneity depends on the deposition angle, when the deposition is made along that direction. 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 minimum at a certain deposition angle off-normal to (001) terrace, and shows a strong correlation with the inhomogeneous deposition flux. The increase of the growth instability is ascribed to the strengthened step Erlich Schwoebel barrier effects that is caused by the enhanced deposition flux near descending step edge due to the steering effect.