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Title: Chemical bonding, interface strength, and oxygen K electron-energy-loss near-edge structure of the Cu/Al{sub 2}O{sub 3} interface

Abstract

Chemical bondings and oxygen K electron-energy-loss near-edge structures (ELNES) of oxygen terminated Cu/Al{sub 2}O{sub 3} heterointerfaces with hollow and on-top configurations were theoretically investigated by using a first principles orthogonalized linear combination of atomic orbitals method. From the chemical bonding analysis, it was found that the hollow configuration has stronger ionic and covalent bondings as compared with the on-top configuration, and the weakness of the on-top configuration originates from the strong antibonding interactions between an interfacial oxygen and the second near neighbor Cu. Detailed analysis using overlap population diagrams revealed the formation mechanism of the strong antibonding interactions in the on-top configuration. In the oxygen K ELNES calculation, a prepeak feature appears in both configurations and it was predicted that the prepeak for the on-top configuration is larger than that for the hollow configuration. The overlap population diagrams elucidated that the prepeak is mainly composed of the O-Cu antibonding interactions, and the larger prepeak of the on-top configuration originates from the larger O-Cu interactions. The dependence of O-K ELNES on the direction of the momentum transfer vector was also discussed. Knowledge of the responsible direction of the momentum transfer vector in relation to the interface orientation was concluded to bemore » indispensable in order to discuss detailed profiles of the ELNES from metal/ceramic heterointerfaces. This study reveals the effect of the atomic configuration of the interface to the chemical bondings, interface strength, and ELNES.« less

Authors:
; ; ;  [1]; ;  [2];  [3]
  1. Institute of Engineering Innovation, The University of Tokyo, Yayoi, Bunkyo, Tokyo 113-8656 (Japan)
  2. Research Institute for Ubiquitous Energy Devices, National Institute of Advanced Industrial Science and Technology, 1-8-31 Midorigaoka, Ikeda 563-8577 (Japan)
  3. Department of Advanced Materials Science, The University of Tokyo, 5-1-5, Kashiwanoha, Kashiwa, Chiba 277-8561 (Japan)
Publication Date:
OSTI Identifier:
20853975
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 74; Journal Issue: 23; Other Information: DOI: 10.1103/PhysRevB.74.235408; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALUMINIUM OXIDES; CERAMICS; CHEMICAL BONDS; COPPER; COVALENCE; ELECTRON SPECTRA; ELECTRONS; ENERGY-LOSS SPECTROSCOPY; INTERFACES; LCAO METHOD; MOMENTUM TRANSFER; ORIENTATION; OXYGEN

Citation Formats

Mizoguchi, Teruyasu, Sasaki, Takeo, Matsunaga, Katsuyuki, Ikuhara, Yuichi, Tanaka, Shingo, Kohyama, Masanori, and Yamamoto, Takahisa. Chemical bonding, interface strength, and oxygen K electron-energy-loss near-edge structure of the Cu/Al{sub 2}O{sub 3} interface. United States: N. p., 2006. Web. doi:10.1103/PHYSREVB.74.235408.
Mizoguchi, Teruyasu, Sasaki, Takeo, Matsunaga, Katsuyuki, Ikuhara, Yuichi, Tanaka, Shingo, Kohyama, Masanori, & Yamamoto, Takahisa. Chemical bonding, interface strength, and oxygen K electron-energy-loss near-edge structure of the Cu/Al{sub 2}O{sub 3} interface. United States. doi:10.1103/PHYSREVB.74.235408.
Mizoguchi, Teruyasu, Sasaki, Takeo, Matsunaga, Katsuyuki, Ikuhara, Yuichi, Tanaka, Shingo, Kohyama, Masanori, and Yamamoto, Takahisa. Fri . "Chemical bonding, interface strength, and oxygen K electron-energy-loss near-edge structure of the Cu/Al{sub 2}O{sub 3} interface". United States. doi:10.1103/PHYSREVB.74.235408.
@article{osti_20853975,
title = {Chemical bonding, interface strength, and oxygen K electron-energy-loss near-edge structure of the Cu/Al{sub 2}O{sub 3} interface},
author = {Mizoguchi, Teruyasu and Sasaki, Takeo and Matsunaga, Katsuyuki and Ikuhara, Yuichi and Tanaka, Shingo and Kohyama, Masanori and Yamamoto, Takahisa},
abstractNote = {Chemical bondings and oxygen K electron-energy-loss near-edge structures (ELNES) of oxygen terminated Cu/Al{sub 2}O{sub 3} heterointerfaces with hollow and on-top configurations were theoretically investigated by using a first principles orthogonalized linear combination of atomic orbitals method. From the chemical bonding analysis, it was found that the hollow configuration has stronger ionic and covalent bondings as compared with the on-top configuration, and the weakness of the on-top configuration originates from the strong antibonding interactions between an interfacial oxygen and the second near neighbor Cu. Detailed analysis using overlap population diagrams revealed the formation mechanism of the strong antibonding interactions in the on-top configuration. In the oxygen K ELNES calculation, a prepeak feature appears in both configurations and it was predicted that the prepeak for the on-top configuration is larger than that for the hollow configuration. The overlap population diagrams elucidated that the prepeak is mainly composed of the O-Cu antibonding interactions, and the larger prepeak of the on-top configuration originates from the larger O-Cu interactions. The dependence of O-K ELNES on the direction of the momentum transfer vector was also discussed. Knowledge of the responsible direction of the momentum transfer vector in relation to the interface orientation was concluded to be indispensable in order to discuss detailed profiles of the ELNES from metal/ceramic heterointerfaces. This study reveals the effect of the atomic configuration of the interface to the chemical bondings, interface strength, and ELNES.},
doi = {10.1103/PHYSREVB.74.235408},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 23,
volume = 74,
place = {United States},
year = {Fri Dec 15 00:00:00 EST 2006},
month = {Fri Dec 15 00:00:00 EST 2006}
}
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