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Mechanisms of misfit strain relaxation in epitaxially grown BLT (Bi4-xLaxTi3O12, x = 0.75) thin films

Published online by Cambridge University Press:  15 February 2011

Hyung Seok Kim ,
Sang Ho Oh ,
Ju Hyung Suh  and
Chan Gyung Park
Hyung Seok Kim
Affiliation:
Department of Material Science & Engineering Pohang University of Science and Technology (POSTECH), Pohang 790-784, Korea
Sang Ho Oh
Affiliation:
Department of Material Science & Engineering Pohang University of Science and Technology (POSTECH), Pohang 790-784, Korea Max-Planck-Institut für Metallforschung, Heisenbergstr. 3, 70569 Stuttgart, Germany
Ju Hyung Suh
Affiliation:
Department of Material Science & Engineering Pohang University of Science and Technology (POSTECH), Pohang 790-784, Korea
Chan Gyung Park
Affiliation:
Department of Material Science & Engineering Pohang University of Science and Technology (POSTECH), Pohang 790-784, Korea
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Abstract

Mechanisms of misfit strain relaxation in epitaxially grown Bi4-xLaxTi3O12 (BLT) thin films deposited on SrTiO3 (STO) and LaAlO3 (LAO) substrates have been investigated by means of transmission electron microscopy (TEM). The misfit strain of 20 nm thick BLT films grown on STO substrate was relaxed by forming misfit dislocations at the interface. However, cracks were observed in 100 nm thick BLT films grown on the same STO. It was confirmed that cracks were formed because of high misfit strain accumulated with increasing the thickness of BLT, that was not sufficiently relaxed by misfit dislocations. In the case of the BLT film grown on LAO substrate, the magnitude of lattice misfit between BLT and LAO was very small (~1/10) in comparison with the case of the BLT grown on STO. The relatively small misfit strain formed in layered structure of the BLT films on LAO, therefore, was easily relaxed by distorting the film, rather than forming misfit dislocations or cracks, resulting in misorientation regions in the BLT film.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 779: Symposium W – Multiscale Phenomena in Materials - Experiments and Modeling Related to Mechanical Behavior , 2003 , W5.23
Copyright
Copyright © Materials Research Society 2003

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References

1. Park, B.H., Kang, B. S., Bu, S. D., Noh, T.W., Lee, J. and Jo, W., Nature, 401, 682 (1999).Google Scholar
2. Lee, H. N., Hesse, D., Zakhalov, N., Gosele, U., Science, 296, 2006 (2002).Google Scholar
3. Nix, W. D., Mechanical properties of thin films, The 1988 Institute of metals lecture, 20A, 2217 (1989).Google Scholar
4. Koster, G., Rijnders, G., Blank, D. H. A., Rogalla, H., Pysica C, 399, 215 (2000).Google Scholar
5. Yao, J., Merrill, P. B., Perry, S. S., Marton, D. and Rabalais, J.W., J. Chem. Phys, 22, 108 (1998).Google Scholar
6. Simons, G. and Wang, H., Single crystal elastic constants and calculated aggregate properties: A handbook (MIT, Cambridge, 1971) p. 238.Google Scholar
7. Yao, G. D., Hou, S. Y., Dudley, M., Phillips, J. M., J. of Mater. Res., 7, 1847 (1992).Google Scholar
8. Song, J.-H., Kim, K. K., Oh, Y. J., Jung, H. J., Song, J. H., Choi, D. k., Choi, W. K., J. of Crystal Growth, 223, 129 (2001).Google Scholar
9. Tsao, J. Y., Materials Fundamentals of Molecular Beam Epitaxy (Academic press Inc., 1993) pp. 93–125.Google Scholar
10. Oh, S. H., Ph. D. Thesis chapter 5, (POSTECH, 2002).Google Scholar