Smoluchowski ripening of Ag islands on Ag(100)

Journal Article · Wed Sep 01 04:00:00 EDT 1999 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.479770· OSTI ID:6469008

Stoldt, C R; Jenks, C J; Thiel, P A ^[1]; Cadilhe, A M ^[2]; Evans, J W ^[3]

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1. Department of Chemistry and Ames Laboratory, Iowa State University, Ames, Iowa 50011 (United States)
2. IPRT and Ames Laboratory, Iowa State University, Ames, Iowa 50011 (United States)
3. Department of Mathematics and Ames Laboratory, Iowa State University, Ames, Iowa 50011 (United States)

Using scanning tunneling microscopy, we study the post-deposition coarsening of distributions of large, two-dimensional Ag islands on a perfect Ag(100) surface at 295 K. The coarsening process is dominated by diffusion, and subsequent collision and coalescence of these islands. To obtain a comprehensive characterization of the coarsening kinetics, we perform [ital tailored families] of experiments, systematically varying the initial value of the average island size by adjusting the amount of Ag deposited (up to 0.25 ML). Results unambiguously indicate a strong decrease in island diffusivity with increasing island size. An estimate of the size scaling exponent follows from a mean-field Smoluchowski rate equation analysis of experimental data. These rate equations also predict a [ital rapid] depletion in the initial population of smaller islands. This leads to narrowing of the size distribution scaling function from its initial form, which is determined by the process of island nucleation and growth during deposition. However, for later times, a steady increase in the width of this scaling function is predicted, consistent with observed behavior. Finally, we examine the evolution of Ag adlayers on a strained Ag(100) surface, and find significantly enhanced rates for island diffusion and coarsening. [copyright] [ital 1999 American Institute of Physics.]

• OSTI ID: 6469008
• Journal Information: Journal of Chemical Physics, Journal Name: Journal of Chemical Physics Vol. 111:11; ISSN JCPSA6; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

665000* -- Physics of Condensed Matter-- (1992-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ADSORBENTS
DEPOSITION
DIFFUSION
ELECTRON MICROSCOPY
ELEMENTS
FILMS
ISLANDS
METALS
MICROSCOPY
NUCLEATION
ROUGHNESS
SCANNING ELECTRON MICROSCOPY
SILVER
SURFACE PROPERTIES
THIN FILMS
TRANSITION ELEMENTS