Hostname: page-component-78c5997874-ndw9j Total loading time: 0 Render date: 2024-11-02T23:40:59.259Z Has data issue: false hasContentIssue false

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
Get access

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

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. See, e.g., Bauer, E.G., Dodson, B.W., Ehrlich, D.J., Feldman, L.C., Flynn, C.P., Geis, M.W., Harbison, J.P., Matyi, R.J., Peercy, P.S., Petroff, P.M., Phillips, J.M., Stringfellow, G.B., and Zangwill, A., J. Mater. Res. 5, 852 (1990).CrossRefGoogle Scholar
2. Clarke, S. and Vvedensky, D.D., Phys. Rev. Lett. 58, 2235 (1987).CrossRefGoogle Scholar
3. Shitara, T., Vvedensky, D.D., Wilby, M.R., Zhang, J., Neave, J.H., and Joyce, B.A., Phys. Rev. B 46, 6815 (1992); T. Shitara, D.D. Vvedensky, M.R. Wilby, J. Zhang, J.H. Neave, and B.A. Joyce, Phys. Rev. B 46, 6825 (1992).CrossRefGoogle Scholar
4. Šmilauer, P., Wilby, M.R., and Vvedensky, D.D., Phys. Rev. B 47, 4119 (1993).CrossRefGoogle Scholar
5. Šmilauer, P., Wilby, M.R., and Vvedensky, D.D., Surf. Sci. (in press).Google Scholar
6. Kunkel, R., Poelsema, B., Verheij, L.K., and Comsa, G., Phys. Rev. Lett. 65, 733 (1990).CrossRefGoogle Scholar
7. Ehrlich, G. and Hudda, F.G., J. Chem. Phys. 44, 1039 (1966).CrossRefGoogle Scholar
8. Fink, H.-W. and Ehrlich, G., Surf. Sci. 143, 125 (1984).CrossRefGoogle Scholar
9.. Poelsema, B., Becker, A.F., Rosenfeld, G., Kunkel, R., Nagel, N., Verheij, L.K., and Comsa, G., Surf. Sci. 272, 269 (1992).CrossRefGoogle Scholar
10. Bott, M., Michely, T., and Comsa, G., Surf. Sci. 272, 161 (1992).CrossRefGoogle Scholar
11. Stoltze, P. and Norskov, J.K. (unpublished).Google Scholar
12. Wang, S.C. and Ehrlich, G., Phys. Rev. Lett. 67, 2509 (1991).CrossRefGoogle Scholar
13. Egelhoff, W.F. Jr. and Jacob, I., Phys. Rev. Lett. 62, 921 (1989).CrossRefGoogle Scholar
14. J. Ferrón, Phys. Rev. B 46, 10457 (1992).CrossRefGoogle Scholar
15. Poelsema, B., Verheij, L.K., and Comsa, G., Phys. Rev. Lett. 53, 2500 (1984); B. Poelsema, L.K. Verheij, and G. Comsa, Phys. Rev. B 41, 11609 (1990).CrossRefGoogle Scholar
16. Michely, T., Land, T., Littmark, U., and Comsa, G., Surf. Sci. 272, 204 (1992).CrossRefGoogle Scholar
17. Neave, J.H., Joyce, B.A., Dobson, P.J., and Norton, N., Appl. Phys. A 31, 1 (1983).CrossRefGoogle Scholar
18. Grunthaner, F.J., Madhukar, A., Lee, T.C., and Fernandez, R., J. Vac. Sci. Technol. B 3, 1317 (1985).Google Scholar
19. Vvedensky, D.D. and Clarke, S., Surf. Sci. 225, 373 (1990).CrossRefGoogle Scholar
20. Yoshinaga, A., Fahy, M., Dosanih, S., Zhang, J., Neave, J.H., and Joyce, B.A., Surf. Sci. 264, L157 (1992).CrossRefGoogle Scholar
21. Peng, L.-M. and Whelan, M.J., Proc. Roy. Soc. London 435, 257 (1991).Google Scholar
22. Quite surprisingly, we found that not only the step-edge barrier but also the incorporation mechanism (the underlying physical mechanism of which is probably quite different from that described above) is an important factor. The incorporation mechanism makes it possible to achieve better agreement between experimental data and simulations both at the onset of growth and during the recovery stage, due to smoothening of island and step edges and reducing the number of free adatoms and very small islands.Google Scholar