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Title: Capillary instabilities in thin films. II. Kinetics

Abstract

We consider the kinetic evolution of perturbations to thin films. Since all small (nonsubstrate intersecting) perturbations to the film surface decay, we consider the evolution of large perturbations, in the form of a single hole which exposes the substrate. For large holes, the hole radius increases at a constant rate under the assumption of evaporation/condensation kinetics. When the dominant transport mode is surface diffusion, large holes grow with a rate proportional to t/sup -3/4/ (log/sup 3/(t/ rho/sup 4//sub c/)). Small holes with a radii less than rho/sub c/ shrink, where rho/sub c/ is the film thickness divided by the tangent of the equilibrium wetting angle. The growth of these holes eventually leads to hole impingement which ruptures the film, creating a set of disconnected islands. The relaxation time for these islands to go to their equilibrium shape and size (rho/sub eq/) scales as rho/sup 2//sub eq/ or rho/sup 4//sub eq/ for evaporation/condensation or surface diffusion kinetics, respectively.

Authors:
;
Publication Date:
Research Org.:
Los Alamos National Laboratory, Los Alamos, New Mexico 87545
OSTI Identifier:
5522181
Resource Type:
Journal Article
Resource Relation:
Journal Name: J. Appl. Phys.; (United States); Journal Volume: 60:1
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; THIN FILMS; DIFFUSION; STABILITY; SURFACE PROPERTIES; CAVITIES; EVAPORATION; FLUCTUATIONS; KINETICS; RELAXATION; FILMS; PHASE TRANSFORMATIONS; VARIATIONS; 656000* - Condensed Matter Physics

Citation Formats

Srolovitz, D.J., and Safran, S.A.. Capillary instabilities in thin films. II. Kinetics. United States: N. p., 1986. Web. doi:10.1063/1.337691.
Srolovitz, D.J., & Safran, S.A.. Capillary instabilities in thin films. II. Kinetics. United States. doi:10.1063/1.337691.
Srolovitz, D.J., and Safran, S.A.. 1986. "Capillary instabilities in thin films. II. Kinetics". United States. doi:10.1063/1.337691.
@article{osti_5522181,
title = {Capillary instabilities in thin films. II. Kinetics},
author = {Srolovitz, D.J. and Safran, S.A.},
abstractNote = {We consider the kinetic evolution of perturbations to thin films. Since all small (nonsubstrate intersecting) perturbations to the film surface decay, we consider the evolution of large perturbations, in the form of a single hole which exposes the substrate. For large holes, the hole radius increases at a constant rate under the assumption of evaporation/condensation kinetics. When the dominant transport mode is surface diffusion, large holes grow with a rate proportional to t/sup -3/4/ (log/sup 3/(t/ rho/sup 4//sub c/)). Small holes with a radii less than rho/sub c/ shrink, where rho/sub c/ is the film thickness divided by the tangent of the equilibrium wetting angle. The growth of these holes eventually leads to hole impingement which ruptures the film, creating a set of disconnected islands. The relaxation time for these islands to go to their equilibrium shape and size (rho/sub eq/) scales as rho/sup 2//sub eq/ or rho/sup 4//sub eq/ for evaporation/condensation or surface diffusion kinetics, respectively.},
doi = {10.1063/1.337691},
journal = {J. Appl. Phys.; (United States)},
number = ,
volume = 60:1,
place = {United States},
year = 1986,
month = 7
}
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  • No abstract prepared.
  • The surface dynamics of thin molten polystyrene films supported by nanoscale periodic silicon line-space gratings were investigated with x-ray photon correlation spectroscopy. Surface dynamics over these nanostructures exhibit high directional anisotropy above certain length scales, as compared to surface dynamics over flat substrates. A cutoff length scale in the dynamics perpendicular to the grooves is observed. This marks a transition from standard over-damped capillary wave behavior to suppressed dynamics due to substrate interactions.