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Title: High-speed nanoscale characterization of dewetting via dynamic transmission electron microscopy

Abstract

The dewetting of thin films can occur in either the solid or the liquid state for which different mass transport mechanisms are expected to control morphological changes. Traditionally, dewetting dynamics have been examined on time scales between several seconds to hours, and length scales ranging between nanometers and millimeters. The determination of mass transport mechanisms on the nanoscale, however, requires nanoscale spatial resolution and much shorter time scales. This study reports the high-speed observation of dewetting phenomena for kinetically constrained Ni thin films on crystalline SrTiO{sub 3} substrates. Movie-mode Dynamic Transmission Electron Microscopy (DTEM) was used for high-speed image acquisition during thin film dewetting at different temperatures. DTEM imaging confirmed that the initial stages of film agglomeration include edge retraction, hole formation, and growth. Finite element modeling was used to simulate temperature distributions within the DTEM samples after laser irradiation with different energies. For pulsed laser irradiation at 18 μJ, experimentally observed hole growth suggests that Marangoni flow dominates hole formation in the liquid nickel film. After irradiation with 13.8 μJ, however, the observations suggest that dewetting was initiated by nucleation of voids followed by hole growth through solid-state surface diffusion.

Authors:
 [1];  [2]; ;  [3];  [1]
  1. Department of Materials Science and Engineering, University of California, Davis, 1 Shields Ave., Davis, California 95616 (United States)
  2. (United States)
  3. Materials Science Division, Lawrence Livermore National Laboratory, 7000 East Ave., Livermore, California 94550 (United States)
Publication Date:
OSTI Identifier:
22598884
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 120; Journal Issue: 8; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ELECTRONS; FINITE ELEMENT METHOD; HOLES; IMAGES; IRRADIATION; LASER RADIATION; LIQUIDS; MORPHOLOGICAL CHANGES; NANOSTRUCTURES; NICKEL; SPATIAL RESOLUTION; STRONTIUM TITANATES; SUBSTRATES; TEMPERATURE DISTRIBUTION; THIN FILMS; TRANSMISSION ELECTRON MICROSCOPY; VELOCITY

Citation Formats

Hihath, Sahar, Department of Physics, University of California, Davis, 1 Shields Ave., Davis, California 95616, Santala, Melissa K., Campbell, Geoffrey, and Benthem, Klaus van, E-mail: benthem@ucdavis.edu. High-speed nanoscale characterization of dewetting via dynamic transmission electron microscopy. United States: N. p., 2016. Web. doi:10.1063/1.4961212.
Hihath, Sahar, Department of Physics, University of California, Davis, 1 Shields Ave., Davis, California 95616, Santala, Melissa K., Campbell, Geoffrey, & Benthem, Klaus van, E-mail: benthem@ucdavis.edu. High-speed nanoscale characterization of dewetting via dynamic transmission electron microscopy. United States. doi:10.1063/1.4961212.
Hihath, Sahar, Department of Physics, University of California, Davis, 1 Shields Ave., Davis, California 95616, Santala, Melissa K., Campbell, Geoffrey, and Benthem, Klaus van, E-mail: benthem@ucdavis.edu. 2016. "High-speed nanoscale characterization of dewetting via dynamic transmission electron microscopy". United States. doi:10.1063/1.4961212.
@article{osti_22598884,
title = {High-speed nanoscale characterization of dewetting via dynamic transmission electron microscopy},
author = {Hihath, Sahar and Department of Physics, University of California, Davis, 1 Shields Ave., Davis, California 95616 and Santala, Melissa K. and Campbell, Geoffrey and Benthem, Klaus van, E-mail: benthem@ucdavis.edu},
abstractNote = {The dewetting of thin films can occur in either the solid or the liquid state for which different mass transport mechanisms are expected to control morphological changes. Traditionally, dewetting dynamics have been examined on time scales between several seconds to hours, and length scales ranging between nanometers and millimeters. The determination of mass transport mechanisms on the nanoscale, however, requires nanoscale spatial resolution and much shorter time scales. This study reports the high-speed observation of dewetting phenomena for kinetically constrained Ni thin films on crystalline SrTiO{sub 3} substrates. Movie-mode Dynamic Transmission Electron Microscopy (DTEM) was used for high-speed image acquisition during thin film dewetting at different temperatures. DTEM imaging confirmed that the initial stages of film agglomeration include edge retraction, hole formation, and growth. Finite element modeling was used to simulate temperature distributions within the DTEM samples after laser irradiation with different energies. For pulsed laser irradiation at 18 μJ, experimentally observed hole growth suggests that Marangoni flow dominates hole formation in the liquid nickel film. After irradiation with 13.8 μJ, however, the observations suggest that dewetting was initiated by nucleation of voids followed by hole growth through solid-state surface diffusion.},
doi = {10.1063/1.4961212},
journal = {Journal of Applied Physics},
number = 8,
volume = 120,
place = {United States},
year = 2016,
month = 8
}
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