KMC simulation of growth and equilibration of V-shaped patterned crystal surface via step motion

Abstract

We study the growth and equilibration of an initially V-shaped surface consisting of monolayer height steps separated by terraces by Kinetic Monte Carlo (KMC) method. Some of the processes that are considered are attachment and/or detachment of particles to/from steps, freely diffusing atoms on the surface and movement of particles along the step or cluster edges. Ehrlich–Schwoebel (ES) barrier effect is also considered. The bottom of the V-shape with respect to flat surface evolves as d(t)~tα where α is approximately 1/2 in the absence of particle flux to the surface and in general 0.5<α<1. It is found that the exponent α depends on both the temperature and the flux rate in the presence of a constant flux of particles to the surface. The lower the temperature and the higher the flux, the higher the value of α is. The shape of the groove also depends both on temperature and on the value of the flux to the surface. For low or no flux to the surface, the bottom of groove becomes rounded. At high values of flux and at low temperatures, the V-shape of the profile is preserved for a long period of time.