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Crystal structure and microstructure of epitaxial Pb(Zr,Ti)O3 films consisting of mixed phases with tetragonal and rhombohedral symmetries grown on (100)cSrRuO3//(100)SrTiO3 substrate by metalorganic chemical vapor deposition

Published online by Cambridge University Press:  31 January 2011

Shintaro Yokoyama ,
Hitoshi Morioka ,
Yong Kwan Kim ,
Hiroshi Nakaki ,
Hiroshi Funakubo ,
Keisuke Saito ,
Ken Nishida  and
Takashi Katoda
Shintaro Yokoyama
Affiliation:
Department of Innovative and Engineered Materials, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, Midori-ku, Yokohama 226-8502, Japan
Hitoshi Morioka
Affiliation:
Department of Innovative and Engineered Materials, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, Midori-ku, Yokohama 226-8502, Japan
Yong Kwan Kim
Affiliation:
Department of Innovative and Engineered Materials, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, Midori-ku, Yokohama 226-8502, Japan
Hiroshi Nakaki
Affiliation:
Department of Innovative and Engineered Materials, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, Midori-ku, Yokohama 226-8502, Japan
Hiroshi Funakubo*
Affiliation:
Department of Innovative and Engineered Materials, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, Midori-ku, Yokohama 226-8502, Japan
Keisuke Saito
Affiliation:
Application Laboratory, Bruker AXS, Kanagawa-ku, Yokohama 221-0022, Japan
Ken Nishida
Affiliation:
Department of Electronic and Photonic Systems Engineering, Kochi University of Technology, Kami-gun, Kochi 782-8502, Japan
Takashi Katoda
Affiliation:
Department of Electronic and Photonic Systems Engineering, Kochi University of Technology, Kami-gun, Kochi 782-8502, Japan
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

(100)-/(001)-oriented epitaxial Pb(Zr,Ti)O3(PZT) films with various Zr/(Zr + Ti) ratios and film thicknesses were grown on (100)cSrRuO3//(100)SrTiO3substrates at 600 °C by metalorganic chemical vapor deposition. Their crystal structure and microstructure consisting of particularly mixed phases with tetragonal and rhombohedral symmetries were investigated in detail. Films with the mixed phases with tetragonal and rhombohedral symmetries were ascertained at a Zr/(Zr + Ti) ratio of around 0.50 at a thickness of more than 200 nm from x-ray diffraction (XRD) analysis, while no mixed phase region was observed for 50 nm thick film. The relative volume fraction of the tetragonal cdomain decreased with increasing film thickness for 2-μm-thick films with mixed phases, while the tetragonal adomain and rhombohedral domain increased. These mixed phases were ascertained to have originated from the same cubic PZT grown above Curie temperature from results obtained by temperature-dependent high-resolution XRD reciprocal space mapping. The transmission electron microscopy images clearly revealed that the microstructure of the film gradually changed along the film thickness, despite the fact that the film was very uniform. Tetragonal phases were dominant in the bottom region (near the interface with the substrate) of the film, while rhombohedral phase was dominant in the upper region (near the surface), which was also ascertained by cross-sectional Raman analysis. In addition, the tetragonal a/cdomain was wider in the bottom region than that in the upper region of film with mixed phases. These data clearly demonstrate that both the crystal structure and microstructure changed along the film thickness.

Keywords

FerroelectricMicrostructureX-ray diffraction (XRD)
Type
Articles
Information
Journal of Materials Research , Volume 22 , Issue 6 , June 2007 , pp. 1551 - 1557
Copyright
Copyright © Materials Research Society2007

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References

REFERENCES

1Jaffe, B., Cook, W.R.Jaffe, H.: Piezoelectric Ceramics(Academic Press, New York, 1971), p. 1Google Scholar
2Oh, S.H.Jang, H.M.: Two-dimensional thermodynamic theory of epitaxial Pb(Zr,Ti)O3thin films. Phys. Rev. B 62, 14757 2000Google Scholar
3Oh, S.H.Jang, H.M.: Epitaxial Pb(Zr, Ti)O3thin films with coexisting tetragonal and rhombohedral phases. Phys. Rev. B 63, 132101 2001Google Scholar
4Yokoyama, S., Honda, Y., Morioka, H., Oikawa, T., Iijima, T., Matsuda, H., Saito, K.Funakubo, H.: Large piezoelectric response in (111)-oriented epitaxial Pb(Zr,Ti)O3films consisting of mixed phases with rhombohedral and tetragonal symmetry. Appl. Phys. Lett. 83, 2408 2003CrossRefGoogle Scholar
5Yokoyama, S., Honda, Y., Morioka, H., Okamoto, S., Iijima, T., Matsuda, H., Saito, K., Yamamoto, T., Okino, H., Sakata, O., Kimura, S.Funakubo, H.: Dependence of electrical properties of epitaxial Pb(Zr,Ti)O3thick films on crystal orientation and Zr/(Zr + Ti) ratio. J. Appl. Phys. 98, 094106 2005CrossRefGoogle Scholar
6Ragini, R., Ranjan, S., Mishra, K.Pandey, D.: Room temperature structure of Pb(ZrxTi1–xO3) around the morphotropic phase boundary region: A Rietveld study. J. Appl. Phys. 92, 3266 2002CrossRefGoogle Scholar
7Yokoyama, S., Honda, Y., Morioka, H., Asano, G., Oikawa, T., Iijima, T., Matsuda, H.Funakubo, H.: Compositional dependence of electrical properties of highly (100)-/(001)-oriented Pb(Zr,Ti)O3thick films prepared on Si substrates by metalorganic chemical vapor deposition. Jpn. J. Appl. Phys. Part 1 42, 5922 2003CrossRefGoogle Scholar
8Morioka, H., Yokoyama, S., Oikawa, T., Saito, K.Funakubo, H.: Growth of epitaxial tetragonal Pb(Zr,Ti)O3thin films with 100% polar-axis-orientation and their electrical properties, in Ferroelectric Thin Films XII,edited by S. Hoffmann-Eifert, H. Funakubo, V. Joshi, A.I. Kingon, and I.P. Koutsaroff (Mater. Res. Soc. Symp. Proc. 784, Warrendale, PA, 2004), C6.2.1CrossRefGoogle Scholar
9Nagashima, K., Aratani, M.Funakubo, H.: Improvement of property of Pb(ZrxTi1−x)O3thin film prepared by source gas pulse-introduced metalorganic chemical vapor deposition. Jpn. J. Appl. Phys., Part 2 39, L996 2000CrossRefGoogle Scholar
10Sumi, A., Takahashi, K., Yokoyama, S., Morioka, H., Yoshimoto, M.Funakubo, H.: Metalorganic chemical vapor deposition of atomically flat SrRuO3films on stepped SrTiO3substrates. Appl. Phys. Lett. 87, 052112 2005CrossRefGoogle Scholar
11Saito, K., Kurosawa, T., Akai, T., Oikawa, T.Funakubo, H.: Structural characterization and 90° domain contribution to ferroelectricity of epitaxial Pb(Zr0.35,Ti0.65)O3thin films. J. Appl. Phys. 93, 545 2003CrossRefGoogle Scholar
12Shirane, G.Suzuki, K.: Crystal structure of Pb(Zr,Ti)O3. J. Phys. Soc. Jpn. 7, 333 1952CrossRefGoogle Scholar
13Burns, G.Scott, B.A.: Evidence for crossover behavior near the soft-mode transition in SrTiO3. Phys. Rev. Lett. 36, 1191 1970CrossRefGoogle Scholar
14Wang, R., Stephenson, G., Fong, D., Jiang, F., Fuoss, P., Eastman, J., Streiffer, S., Latifi, K.Thompson, C.: Real time x-ray observation of lattice pulling during growth of epitaxial Pb(Zr,Ti)O3films. Appl. Phys. Lett. 89, 221914 2006CrossRefGoogle Scholar
15Kelman, M., McIntyre, P., Hendrix, B., Bilodeau, S., Roeder, J.Brennan, S.: Structural analysis of coexisting tetragonal and rhombohedral phases in polycrystalline Pb(Zr0.35Ti0.65)O3thin films. J. Mater. Res. 18, 173 2003CrossRefGoogle Scholar
16Yokoyama, S., Okamoto, S., Saito, K., Iijima, T., Okino, H., Yamamoto, T., Nishida, K., Katoda, T., Sakai, J.Funakubo, H.: Characteristic Comparison of Epitaxial PZT And PMN-PT Films Grown on (100)cSrRuO3//(100)SrTiO3Substrates By Metalorganic Chemical Vapor Deposition, in Ferroelectric Thin Films XIII, edited by R. Ramesh, J.-P. Maria, M. Alexe, V. Joshi (Mater. Res. Soc. Symp. Proc. 902E, Warrendale, PA, 2006), 0902-T03-29.1Google Scholar