Step Motion on Crystal Surfaces. II

TLDR

The capture and detachment of atoms at surface steps is considered to occur with arbitrary probability. A theory for step motion on crystal surfaces undergoing growth, evaporation, and annealing is described. The conditions under which the kinetic and quasiequilibrium considerations apply are given in terms of the capture and detachment rate constants. Differences in capture and/or detachment probabilities produce key step‑motion characteristics, and sinusoidally stepped surfaces smooth or roughen during growth or evaporation as macroscopic capillarity theory predicts.

Abstract

A theory for step motion on crystal surfaces undergoing growth, evaporation, and annealing is described. The capture and detachment of atoms at surface steps is considered to occur with arbitrary probability. It is shown that differences in the capture and/or detachment probabilities lead to important characteristics of the step motion. Surfaces with sinusoidally distributed steps will smooth or roughen during growth or evaporation in the same manner as predicted by macroscopic capillarity theory. The conditions under which the kinetic and quasiequilibrium considerations apply are given in terms of the capture and detachment rate constants.