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Title: Surface termination structure of α-Ga{sub 2}O{sub 3} film grown by mist chemical vapor deposition

Abstract

The surface structure of α-Ga{sub 2}O{sub 3}(0001) grown on an α-Al{sub 2}O{sub 3}(0001) substrate by mist chemical vapor deposition was studied by coaxial impact-collision ion scattering spectroscopy (CAICISS) and atomic force microscopy (AFM). The minimum step height observed in the AFM image was 0.21 ± 0.01 nm, coinciding with the height of three atomic layers of α-Ga{sub 2}O{sub 3}(0001). It was revealed by CAICISS analysis that the surface of α-Ga{sub 2}O{sub 3}(0001) is terminated by a Ga layer followed by an O layer, which is consistent with the surface termination of α-Al{sub 2}O{sub 3}(0001). A structural model taking surface relaxation into account was also constructed by fitting the simulated curve for the azimuth angle dependence of the Ga intensity to the experimental dependence. The resultant structural model is similar to the model of an α-Al{sub 2}O{sub 3}(0001) surface, which indicates analogous behavior in corundum crystals.

Authors:
; ; ; ; ;  [1];  [2];  [3]; ;  [2]
  1. Division of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka University, Suita 565-0871 (Japan)
  2. Photonics and Electronics Science and Engineering Center, Graduate School of Engineering, Kyoto University, Kyoto 615-8520 (Japan)
  3. (Japan)
Publication Date:
OSTI Identifier:
22590813
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 108; Journal Issue: 25; 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; ALUMINIUM OXIDES; ATOMIC FORCE MICROSCOPY; CHEMICAL VAPOR DEPOSITION; CORUNDUM; CRYSTALS; DIAGRAMS; FILMS; GALLIUM OXIDES; LAYERS; SPACE DEPENDENCE; STRUCTURAL MODELS; SURFACES

Citation Formats

Tamba, Daiki, Kubo, Osamu, E-mail: okubo@eei.eng.osaka-u.ac.jp, Osaka, Shun, Takahashi, Kazuki, Tabata, Hiroshi, Katayama, Mitsuhiro, Oda, Masaya, FLOSFIA Inc., 1-36 Goryoohara, Kyoto 615-8245, Kaneko, Kentaro, and Fujita, Shizuo. Surface termination structure of α-Ga{sub 2}O{sub 3} film grown by mist chemical vapor deposition. United States: N. p., 2016. Web. doi:10.1063/1.4954673.
Tamba, Daiki, Kubo, Osamu, E-mail: okubo@eei.eng.osaka-u.ac.jp, Osaka, Shun, Takahashi, Kazuki, Tabata, Hiroshi, Katayama, Mitsuhiro, Oda, Masaya, FLOSFIA Inc., 1-36 Goryoohara, Kyoto 615-8245, Kaneko, Kentaro, & Fujita, Shizuo. Surface termination structure of α-Ga{sub 2}O{sub 3} film grown by mist chemical vapor deposition. United States. doi:10.1063/1.4954673.
Tamba, Daiki, Kubo, Osamu, E-mail: okubo@eei.eng.osaka-u.ac.jp, Osaka, Shun, Takahashi, Kazuki, Tabata, Hiroshi, Katayama, Mitsuhiro, Oda, Masaya, FLOSFIA Inc., 1-36 Goryoohara, Kyoto 615-8245, Kaneko, Kentaro, and Fujita, Shizuo. 2016. "Surface termination structure of α-Ga{sub 2}O{sub 3} film grown by mist chemical vapor deposition". United States. doi:10.1063/1.4954673.
@article{osti_22590813,
title = {Surface termination structure of α-Ga{sub 2}O{sub 3} film grown by mist chemical vapor deposition},
author = {Tamba, Daiki and Kubo, Osamu, E-mail: okubo@eei.eng.osaka-u.ac.jp and Osaka, Shun and Takahashi, Kazuki and Tabata, Hiroshi and Katayama, Mitsuhiro and Oda, Masaya and FLOSFIA Inc., 1-36 Goryoohara, Kyoto 615-8245 and Kaneko, Kentaro and Fujita, Shizuo},
abstractNote = {The surface structure of α-Ga{sub 2}O{sub 3}(0001) grown on an α-Al{sub 2}O{sub 3}(0001) substrate by mist chemical vapor deposition was studied by coaxial impact-collision ion scattering spectroscopy (CAICISS) and atomic force microscopy (AFM). The minimum step height observed in the AFM image was 0.21 ± 0.01 nm, coinciding with the height of three atomic layers of α-Ga{sub 2}O{sub 3}(0001). It was revealed by CAICISS analysis that the surface of α-Ga{sub 2}O{sub 3}(0001) is terminated by a Ga layer followed by an O layer, which is consistent with the surface termination of α-Al{sub 2}O{sub 3}(0001). A structural model taking surface relaxation into account was also constructed by fitting the simulated curve for the azimuth angle dependence of the Ga intensity to the experimental dependence. The resultant structural model is similar to the model of an α-Al{sub 2}O{sub 3}(0001) surface, which indicates analogous behavior in corundum crystals.},
doi = {10.1063/1.4954673},
journal = {Applied Physics Letters},
number = 25,
volume = 108,
place = {United States},
year = 2016,
month = 6
}
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