The results of atomic force microscopic measurements of {101} faces showed that, for supersaturations ranging from 3 to 30%, the terrace widths on vicinal growth hillocks - formed by dislocations - were nearly independent of both the supersaturation and the dislocation structure. This contradicted the predictions of simple Burton-Cabrera-Frank models. The data also showed that, for Burgers vectors greater than one unit step-height, the dislocations had hollow cores; in accordance with theoretical predictions. Both analytical and numerical analyses showed that a model which took account of the effect of these cores, upon the period of step rotation, predicted a dependence of the slope upon supersaturation and Burgers vector. This conclusion was in good agreement with experimental results. The calculations also showed that the effect of the core perimeter upon step transit-time predominated over the effect of a reduced step velocity that was due to stresses near to the core. A simple analytical expression could therefore be used to describe the slope; even in the case of anisotropic step kinetics. The results were used to explain the reproducible nature of the macroscopic growth rates, and to re-scale growth-rate data - for various temperatures and supersturations - so that they could be fitted by a single curve.

J.J.De Yoreo, T.A.Land, L.N.Rashkovich, T.A.Onischenko, J.D.Lee, O.V.Monovskii, N.P.Zaitseva: Journal of Crystal Growth, 1997, 182, 442-60