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Hopping Barriers at Step Edges

Published online by Cambridge University Press:  15 February 2011

Pavel Šmilauer
Affiliation:
Interdisciplinary Research Centre for Semiconductor Materials, Imperial College, London SW7 2BZ, United Kingdom
Mark R. Wilby
Affiliation:
The Blackett Laboratory, Imperial College, London SW7 2BZ, United Kingdom
Dimitri D. Vvedensky
Affiliation:
The Blackett Laboratory, Imperial College, London SW7 2BZ, United Kingdom
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Abstract

The recent discovery of reentrant layer-by-layer growth in metal homoepitaxy has stimulated considerable interest in the role played by barriers to hopping down descending steps. However, the existence of step-edge barriers for semiconductors is far from being clearly established. We have investigated the effects of step-edge barriers for epitaxial growth and the “inverse” process of low-energy ion sputtering on metal surfaces using Monte Carlo simulations of a solid-on-solid model. Our results are in good agreement with available experimental data and provide new insights into the microscopic origins of the evolution of surface morphology during these processes. Our simulations also suggest that such step-edge barriers can explain the observed temperature and time dependence of the reflection high-energy electron diffraction intensity during post-growth recovery on GaAs(001), which sheds new light on this controversial subject.

Type
Research Article
Copyright
Copyright © Materials Research Society 1993

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