Hostname: page-component-78c5997874-g7gxr Total loading time: 0 Render date: 2024-11-20T00:05:23.326Z Has data issue: false hasContentIssue false

Interfacial structures of Y123 and Nd123 films formed on MgO(001) substrates by liquid phase epitaxy

Published online by Cambridge University Press:  03 March 2011

J.S. Matsuda*
Affiliation:
Institute of Engineering Innovation, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan
F. Oba
Affiliation:
Institute of Engineering Innovation, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan
T. Murata
Affiliation:
Institute of Engineering Innovation, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan
T. Yamamoto
Affiliation:
Institute of Engineering Innovation, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan
Y. Ikuhara
Affiliation:
Institute of Engineering Innovation, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan
M. Mizuno
Affiliation:
Science and Technology Center for Atoms, Molecules and Ions Control, Osaka University, Suita, Osaka 565-0871, Japan
K. Nomura
Affiliation:
Superconductivity Research Laboratory, ISTEC, Koto-ku, Tokyo 135-0062, Japan
T. Izumi
Affiliation:
Superconductivity Research Laboratory, ISTEC, Koto-ku, Tokyo 135-0062, Japan
Y. Shiohara
Affiliation:
Superconductivity Research Laboratory, ISTEC, Koto-ku, Tokyo 135-0062, Japan
*
a)Address all correspondence to this author.Present Address: Superconductivity Research Laboratory, ISTEC, Koto-ku, Tokyo, B5-0062, Japane-mail: [email protected]
Get access

Abstract

Interfacial structures of c-axis-oriented YBa2Cu3O7–y (Y123) and Nd1+xBa2–xCu3O7–y (Nd123) films were investigated by high-resolution transmission electron microscopy (HRTEM) in conjunction with geometrical lattice matching and molecular orbital calculations. These films were formed on MgO(001) substrates by liquid-phase epitaxy. Despite the similarity in lattice constants between Y123 and Nd123, the in-plane orientation relationship (OR) to the substrates is different: [100]film//[100]substrate(I) for Y123 and [110]film//[100]substrate(II) for Nd123. From the results of HRTEM observations and image simulations, it was found that the Y123 and Nd123 films are terminated by BaO and CuO-chain layers at the interfaces, respectively. For both the Y123/MgO and Nd123/MgO systems, the OR(I) is assessed to be the most favorable in point of geometrical matching and the OR(II) is the second among the rotational misorientations on the [001]film and [001]MgO. The molecular orbital calculations reveal that the interface with the OR(II) and the CuO-chain layer termination is preferable in terms of covalent bonding for both the systems. Consequently, we suggest that the preferential interfacial structures are delicately determined by a balance of the geometrical and chemical factors at the interfaces, resulting in making the lowest interfacial free energies.

Type
Articles
Copyright
Copyright © Materials Research Society 2004

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1.Alarco, J.A., Brorsson, G., Ivanov, Z.G., Nilson, P.A., Olsson, E. andLofgren, M.: Effects of substrate temperature on the microstructure of YBa2Cu3O7–d films grown on (001) Y-ZrO2 substrates. Appl. Phys. Lett. 61 723 (1992).CrossRefGoogle Scholar
2.Tietz, A.L., Carter, C.B., Lathrop, D.K., Russek, S.E., Buhrman, R.A. andMichael, J.R.: Crystallography of YBa2Cu3O6+ x thin film-substrate interfacesJ. Mater. Res. 4 1072 (1989).CrossRefGoogle Scholar
3.Pennycook, S.J., Chisholm, M.F., Jesson, D.E., Feenstra, R., Zhu, S., Zheng, X.Y. andLowndes, D.J.: Growth and relaxation mechanisms of YBa2Cu3O7- x films. Physica C 202 1 (1992).CrossRefGoogle Scholar
4.Traeholt, C., Wen, J.G., Svetchnikov, V. andZandbergen, H.W.: HREM study of the YBCO/MgO interface on an atomic scale. Physica C 230 297 (1994).CrossRefGoogle Scholar
5.Wen, J.G., Ttaeholt, C. andZandbergen, H.W.: Stacking sequence of YBa2Cu3O7 thin film on SrTiO3 substrate. Physica C 205 354 (1993).CrossRefGoogle Scholar
6.Wu, Y., Hao, Z., Enomoto, Y. andTanabe, K.: Atomic configurations of YBa2Cu3O7- x/MgO interfaces. Physica C 371 309 (2002).CrossRefGoogle Scholar
7.Nomura, K., Hoshi, S., Yao, X., Kakimoto, K., Nakamura, Y., Izumi, T. andShiohara, Y.: Preferential growth mechanism of REBa2Cu3O y (RE = Y, Nd) crystal on MgO substrate by liquid phase epitaxy. J. Mater. Res. 16 979 (2001).CrossRefGoogle Scholar
8.Nomura, K., Hoshi, S., Nakamura, Y., Izumi, T. andShiohara, Y.: Initial growth mechanism of YBa2Cu3Oy crystal on MgO substrate by liquid-phase epitaxy. J. Mater. Res. 16 2947 (2001).CrossRefGoogle Scholar
9.Kakimoto, K., Sugawara, Y., Izumi, T. andShiohara, Y.: Initial growth mechanism of YBCO films in liquid phase epitaxy process. Physica C 334, 249 (2000).CrossRefGoogle Scholar
10.Kilaas, R.: HREM image simulation, in Proceedings of the 49th Annual Meeting of the Electron Microscopy Society of America, edited by Bailey, G.W. (San Francisco Press, San Francisco, CA, 1991), p. 528.Google Scholar
11.Ikuhara, Y., Pirouz, P., Heuer, A.H., Yadavalli, S. andFlynn, C.P.: Structure of V-Al2O3 interfaces grown by molecular beam epitaxy. Philos. Mag. A 70 75 (1994).CrossRefGoogle Scholar
12.Ikuhara, Y. andPirouz, P.: High resolution transmission electron microscopy studies on metal/ceramics interfaces. Microsc. Res. Tech. 40 206 (1998).3.0.CO;2-S>CrossRefGoogle ScholarPubMed
13.Mulliken, R.S.: Electronic population analysis on LCAO-MO molecular wave functions. I. J. Chem. Phys. 23 1833 (1995).CrossRefGoogle Scholar
14.Adachi, H., Tsukada, M. andSatoko, C.: Discrete variational X-alpha cluster calculations. 1. Application to metal clusters. J. Phys. Soc. Jpn. 45 875 (1978).CrossRefGoogle Scholar
15.Ellis, D.E., Adachi, H. andAverill, F.W.: Molecular cluster theory for chemisorption of 1st row atoms on nickel(100) surfaces. Surf. Sci. 58 497 (1976).CrossRefGoogle Scholar
16.Tanaka, I., Mizuno, M., Nakajyo, S. andAdachi, H.: Importance of metal-metal bondings at the interface of MgO and 3d-transition metals. Acta Mater. 46 6511 (1998).CrossRefGoogle Scholar