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Title: Microstructure of Co/X (X=Cu,Ag,Au) epitaxial thin films grown on Al{sub 2}O{sub 3}(0001) substrates

Abstract

Epitaxial thin films of Co/X (X=Cu,Ag,Au) were prepared on Al{sub 2}O{sub 3}(0001) substrates at substrate temperatures of 100 and 300 degree sign C by UHV molecular beam epitaxy. A complicated microstructure was realized for the epitaxial thin films. In-situ reflection high-energy electron diffraction observation has shown that X atoms of the buffer layer segregated to the surface during Co layer deposition, and it yielded a unique epitaxial granular structure. The structure consists of small Co grains buried in the X buffer layer, where both the magnetic small Co grains and the nonmagnetic X layer are epitaxially grown on the single crystal substrate. The structure varied depending on the X element and the substrate temperature. The crystal structure of Co grains is influenced by the buffer layer material and determined to be hcp and fcc structures for the buffer layer materials of Au and Cu, respectively.

Authors:
; ; ;  [1];  [2]
  1. Faculty of Science and Engineering, Chuo University, Bunkyo-ku, Tokyo 112-8551 (Japan)
  2. (Japan)
Publication Date:
OSTI Identifier:
20982857
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 9; Conference: 10. joint MMM/INTERMAG conference, Baltimore, MD (United States), 7-11 Jan 2007; Other Information: DOI: 10.1063/1.2712956; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALUMINIUM OXIDES; COBALT; COPPER; CRYSTAL GROWTH; DEPOSITION; ELECTRON DIFFRACTION; FCC LATTICES; FERROMAGNETIC MATERIALS; GOLD; HCP LATTICES; LAYERS; MICROSTRUCTURE; MOLECULAR BEAM EPITAXY; MONOCRYSTALS; SEGREGATION; SILVER; SUBSTRATES; THIN FILMS

Citation Formats

Ohtake, Mitsuru, Akita, Yuta, Futamoto, Masaaki, Kirino, Fumiyoshi, and Graduate School of Fine Arts, Tokyo National University of Fine Arts and Music, Taito-ku, Tokyo 110-8714. Microstructure of Co/X (X=Cu,Ag,Au) epitaxial thin films grown on Al{sub 2}O{sub 3}(0001) substrates. United States: N. p., 2007. Web. doi:10.1063/1.2712956.
Ohtake, Mitsuru, Akita, Yuta, Futamoto, Masaaki, Kirino, Fumiyoshi, & Graduate School of Fine Arts, Tokyo National University of Fine Arts and Music, Taito-ku, Tokyo 110-8714. Microstructure of Co/X (X=Cu,Ag,Au) epitaxial thin films grown on Al{sub 2}O{sub 3}(0001) substrates. United States. doi:10.1063/1.2712956.
Ohtake, Mitsuru, Akita, Yuta, Futamoto, Masaaki, Kirino, Fumiyoshi, and Graduate School of Fine Arts, Tokyo National University of Fine Arts and Music, Taito-ku, Tokyo 110-8714. Tue . "Microstructure of Co/X (X=Cu,Ag,Au) epitaxial thin films grown on Al{sub 2}O{sub 3}(0001) substrates". United States. doi:10.1063/1.2712956.
@article{osti_20982857,
title = {Microstructure of Co/X (X=Cu,Ag,Au) epitaxial thin films grown on Al{sub 2}O{sub 3}(0001) substrates},
author = {Ohtake, Mitsuru and Akita, Yuta and Futamoto, Masaaki and Kirino, Fumiyoshi and Graduate School of Fine Arts, Tokyo National University of Fine Arts and Music, Taito-ku, Tokyo 110-8714},
abstractNote = {Epitaxial thin films of Co/X (X=Cu,Ag,Au) were prepared on Al{sub 2}O{sub 3}(0001) substrates at substrate temperatures of 100 and 300 degree sign C by UHV molecular beam epitaxy. A complicated microstructure was realized for the epitaxial thin films. In-situ reflection high-energy electron diffraction observation has shown that X atoms of the buffer layer segregated to the surface during Co layer deposition, and it yielded a unique epitaxial granular structure. The structure consists of small Co grains buried in the X buffer layer, where both the magnetic small Co grains and the nonmagnetic X layer are epitaxially grown on the single crystal substrate. The structure varied depending on the X element and the substrate temperature. The crystal structure of Co grains is influenced by the buffer layer material and determined to be hcp and fcc structures for the buffer layer materials of Au and Cu, respectively.},
doi = {10.1063/1.2712956},
journal = {Journal of Applied Physics},
number = 9,
volume = 101,
place = {United States},
year = {Tue May 01 00:00:00 EDT 2007},
month = {Tue May 01 00:00:00 EDT 2007}
}
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