Campus Units

Chemistry, Mathematics, Ames Laboratory

Document Type

Article

Publication Version

Published Version

Publication Date

4-2003

Journal or Book Title

Journal of Chemical Physics

Volume

118

Issue

14

First Page

6467

Last Page

6472

DOI

10.1063/1.1558035

Abstract

Preexposure to molecular oxygen gas, O2,g , can have a strong effect on the nucleation and growth of Ag islands on Ag(100) at 250 K. At this temperature, molecular oxygen dissociates efficiently at kink sites on steps. Subsequent deposition of Ag produces a far lower density of Agad islands than without oxygen. There is an associated increase in the Ag flux-scaling exponent, from 0.28 for the oxygen-free surface to 0.9 for the preexposed surface. Two-step deposition experiments show that species containing atomic oxygen diffuse freely across terraces and steps at this temperature and on the time scale of deposition.We hypothesize that the nucleating species contains both Ag and O, and that nucleation of islands is highly reversible ~critical size i>>1). The diffusion of small islands, if it occurs, is not sufficient to explain the data.

Comments

The following article appeared in Journal of Chemical Physics 118, 14 (2003): 6467 and may be found at doi:10.1063/1.1558035.

Rights

Copyright 2003 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics.

Copyright Owner

American Institute of Physics

Language

en

File Format

application/pdf

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