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J. Japan Inst. Metals, Vol. 69, No. 1 (2005), pp. 86_89
Special Issue on Nano_Coating
Ý 2005 The Japan Institute of Metals
ELNES Analysis of Local Electronic Structures at Cu/Al2O3(0001) Interface
Takeo Sasaki1,Þ, Teruyasu Mizoguchi2, Katsuyuki Matsunaga2, Shingo Tanaka3,
Takahisa Yamamoto4, Masanori Kohyama3 and Yuichi Ikuhara2
1Department
of Materials Engineering, School of Engineering, The University of Tokyo, Tokyo 113_
8656
2Institute
of Engineering Innovation, The University of Tokyo, Tokyo 113_8656
3Research
Institute for Ubiquitous Energy Devices, National Institute of Advanced Industrial Science and Technology, Osaka 563_8577
4Department
of Advanced Materials Science, The University of Tokyo, Chiba 277_8651
High_
resolution transmission electron microscopy (HRTEM) observation was performed for a Cu/Al2O3(0001) interface
fabricated by a pulsed laser deposition method to investigate the orientation relationship and atomic structure. The interface elec­
tronic structure was studied by nano_probe electron energy loss spectroscopy (EELS), and the obtained electron energy loss near
edge structure (ELNES) was analyzed by the first_principles calculations. It was found that Cu was epitaxially oriented to the
Al2O3(0001) surface, and the following orientation relationship was observed: (111)Cu//(0001)Al2O3, [1 ˜10]Cu//[1 ˜100]Al2O3. The
experimental O_
K ELNES exhibited a shoulder before the main peak, which was consistent with the theoretical spectrum for the
interface. The shoulder is thought to originate from the Cu_
O interaction across the interface.
(Received September 6, 2004; Accepted October 12, 2004)
Keywords: Cu/Al2O3 interface, atomic structure, chemical bonding states, high_
resolution transmission electron microscopy, electron
energy loss spectroscopy, first_principles calculation, energy loss near edge structure
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sets are enlarged HRTEM images of both hollow and on_top
sites, where the atomic configurations are superimposed.
88
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Fig. 2 Experimental O_K ELNES from (a) the Cu/Al2O3
(0001) interface and (b) Al2O3 bulk.
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Fig. 3 Theoretical O_K ELNES from (a) the Cu/Al2O3
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