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Island Size and Environment Dependence of Adatom Capture: Cu/Co Islands on Ru(0001)

Published online by Cambridge University Press:  10 February 2011

M.C. Bartelt ,
J.W. Evans ,
A.K. Schmid  and
R.Q. Hwang
M.C. Bartelt
Affiliation:
Sandia National Laboratories, Livermore, CA 94550
J.W. Evans
Affiliation:
Iowa State University, Department of Mathematics and Ames Laboratory, Ames, IA 50011
A.K. Schmid
Affiliation:
Sandia National Laboratories, Livermore, CA 94550
R.Q. Hwang
Affiliation:
Sandia National Laboratories, Livermore, CA 94550
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Abstract

The rate of capture by stable Co islands on Ru(0001) of additionally deposited Cu atoms is quantified using scanning tunneling microscopy, kinetic Monte Carlo simulations, and diffusion equation analyses. We find strong dependence of the capture rates on Co-island size, larger islands showing larger capture rates, qualitatively distinct from self-consistent mean-field predictions. The observed size dependence is shown to reflect larger island-free areas surrounding bigger islands, i.e., a strong correlation between island sizes and separations neglected in mean-field treatments.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 528: Symposia AA – Mechanisms & Principals of Epitaxial Growth in Metallic Systems , 1998 , 253
Copyright
Copyright © Materials Research Society 1998

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References

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