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Microstructure of Epitaxial SrTiO3/Pt/Ti/ Sapphire Heterostructures

Published online by Cambridge University Press:  03 March 2011

Steffen Schmidt
Affiliation:
Materials Department, University of California, Santa Barbara, California 93106-5050
Young-Woo Ok
Affiliation:
Materials Department, University of California, Santa Barbara, California 93106-5050
Dmitri O. Klenov
Affiliation:
Materials Department, University of California, Santa Barbara, California 93106-5050
Jiwei Lu
Affiliation:
Materials Department, University of California, Santa Barbara, California 93106-5050
Sean P. Keane
Affiliation:
Materials Department, University of California, Santa Barbara, California 93106-5050
Susanne Stemmer*
Affiliation:
Materials Department, University of California, Santa Barbara, California 93106-5050
*
b) Address all correspondence to this author. e-mail: [email protected]
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Abstract

The microstructure and orientation relationships of epitaxial (111)-oriented SrTiO3 thin films grown by radio frequency magnetron sputtering on epitaxial (111)-oriented Pt/Ti electrodes on sapphire were investigated using x-ray diffraction, conventional and scanning transmission electron microscopy. We show that the epitaxial growth of (111)-oriented SrTiO3 films was promoted by thin Ti adhesion layers underneath the Pt electrode. The SrTiO3 films nucleated with two twin-related orientation variants, rotated by 180° about the 〈111〉 surface normal. The twin boundaries were oriented approximately normal to the film plane, but no strong preference for a specific boundary plane was observed. Growth mechanisms and the relationships to the dielectric properties are discussed.

Type
Rapid Communications
Copyright
Copyright © Materials Research Society 2005

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References

REFERENCES

1Dimos, D. and Mueller, C.H.: Perovskite thin films for high-frequency capacitor applications. Annu. Rev. Mater. Sci. 28, 397 (1998).CrossRefGoogle Scholar
2Tagantsev, A.K., Sherman, V.O., Astafiev, K.F., Venkatesh, J. and Setter, N.: Ferroelectric materials for microwave tunable applications. J. Electroceram. 11, 5 (2003).CrossRefGoogle Scholar
3Xi, X.X., Li, H.C., Si, W.D., Sirenko, A.A., Akimov, I.A., Fox, J.R., Clark, A.M. and Hao, J.H.: Oxide thin films for tunable microwave devices. J. Electroceram. 4, 393 (2000).CrossRefGoogle Scholar
4Dube, D.C., Baborowski, J., Muralt, P. and Setter, N.: The effect of bottom electrode on the performance of thin film based capacitors in the gigahertz region. Appl. Phys. Lett. 74, 3546 (1999).CrossRefGoogle Scholar
5Hwang, C.S., Vaudin, M.D. and Schenck, P.K.: Influence of the microstructure of Pt/Si substrates on textured growth of barium titanate thin films prepared by pulsed laser deposition. J. Mater. Res. 13, 368 (1998).CrossRefGoogle Scholar
6Bilodeau, S.M., Carl, R., Van Buskirk, P.C., Roeder, J.F., Basceri, C., Lash, S.E., Parker, C.B., Streiffer, S.K. and Kingon, A.I.: Dielectric properties and microstructure of thin BST films. J. Korean Phys. Soc. 32, S1591 (1998).Google Scholar
7Kotecki, D.E., Baniecki, J.D., Shen, H., Laibowitz, R.B., Saenger, K.L., Lian, J.J., Shaw, T.M., Athavale, S.D., Cabral, C., Duncombe, P.R., Gutsche, M., Kunkel, G., Park, Y.J., Wang, Y.Y. and Wise, R.: (Ba,Sr) TiO3 dielectrics for future stacked-capacitor DRAM. IBM J. Res. Dev. 43, 367 (1999).CrossRefGoogle Scholar
8Komatsu, S. and Abe, K.: Crystallographic orientation dependence of dielectric constant in epitaxially grown SrTiO3 films. Jpn. J. Appl. Phys. Part 1 34, 3597 (1995).CrossRefGoogle Scholar
9Schmidt, S., Lu, J.W., Keane, S.P., Bregante, L.D., Klenov, D.O. and Stemmer, S.: Microstructure and dielectric properties of textured SrTiO3 thin films. J. Am. Ceram. Soc. 88, 789 (2005).CrossRefGoogle Scholar
10Farrow, R.F.C., Harp, G.R., Marks, R.F., Rabedeau, T.A., Toney, M.F., Weller, D. and Parkin, S.S.P.: Epitaxial growth of Pt on basal-plane sapphire—a seed film for artificially layered magnetic metal structures. J. Cryst. Growth 133, 47 (1993).CrossRefGoogle Scholar
11Ramanathan, S., Clemens, B.M., McIntyre, P.C. and Dahmen, U.: Microstructural study of epitaxial platinum and permalloy/platinum films grown on (0001) sapphire. Philos. Mag. A 81, 2073 (2001).CrossRefGoogle Scholar
12Tunstall, W.J., Steeds, J. and Hirsch, P.B.: Effects of surface stress relaxation on electron microscope images of dislocations normal to thin metal foils. Philos. Mag. 9, 99 (1964).CrossRefGoogle Scholar
13Saylor, D.M., Dasher, B.E., Sano, T. and Rohrer, G.S.: Distribution of grain boundaries in SrTiO3 as a function of five macroscopic parameters. J. Am. Ceram. Soc. 87, 670 (2004).CrossRefGoogle Scholar
14Tani, T., Xu, Z. and Payne, D.A.: Preferred orientations for sol-gel derived PLZT thin layers, in Ferroelectric Thin Films III, edited by Myers, E.R., Tuttle, B.A., Desu, S.B., and Larsen, P.K. (Mater. Res. Soc. Symp. Proc. 310, Pittsburgh, PA, 1993), p. 269.Google Scholar
15Aoki, K., Fukuda, Y., Numata, K. and Nishimura, A.: Effects of titanium buffer layer on lead-zirconate-titanate crystallizations processes in sol-gel deposition technique. Jpn. J. Appl. Phys. Part 1 34, 192 (1995).CrossRefGoogle Scholar
16Muralt, P., Maeder, T., Sagalowicz, L., Hiboux, S., Scalese, S., Naumovic, D., Agostino, R.G., Xanthopoulos, N., Mathieu, H.J., Patthey, L. and Bullock, E.L.: Texture control of PbTiO3 and Pb(Zr,Ti)O3 thin films with TiO2 seeding. J. Appl. Phys. 83, 3835 (1998).CrossRefGoogle Scholar
17DiBattista, M. and Schwenk, J.W.: Determination of diffusion in polycrystalline platinum thin films. J. Appl. Phys. 86, 4902 (1999).CrossRefGoogle Scholar
18Fox, G.R., Trolier-McKinstry, S., Krupanidhi, S.B. and Casas, L.M.: Pt/Ti/SiO2/Si substrates. J. Mater. Res. 10, 1508 (1995).CrossRefGoogle Scholar
19Recnik, A.: Twin in barium titanate. Acta Chim. Slov. 48, 1 (2001).Google Scholar
20Hutt, S., Köstlmeier, S. and Elsässer, C.: Density functional study of the ∑3 (111)[1-10] symmetrical tilt grain boundary in SrTiO3. J. Phys.: Condens. Matter 13, 3949 (2001).Google Scholar
21Astala, R. and Bristowe, P.D.: First-principle calculations of an oxygen deficient ∑ = 3(111)[101] grain boundary in strontium titanate. J. Phys.: Condens. Matter 14, 6455 (2002).Google Scholar
22Canedy, C.L., Li, H., Alpay, S.P., Salamanca-Riba, L., Roytburd, A.L. and Ramesh, R.: Dielectric properties in heteroepitaxial Ba0.6Sr0.4TiO3 thin films: Effect of internal stresses and dislocation-type defects. Appl. Phys. Lett. 77, 1695 (2000).CrossRefGoogle Scholar
23Myhajlenko, S., Bell, A., Ponce, F., Edwards, J.L., Wei, Y., Craigo, B., Convey, D., Li, H., Liu, R. and Kulik, J.: Optoelectronic and microstructure attributes of epitaxial SrTiO3 on Si. J. Appl. Phys. 97, 014101 (2005).CrossRefGoogle Scholar
24Srikant, V., Speck, J.S. and Clarke, D.R.: Mosaic structure in epitaxial thin films having large lattice mismatch. J. Appl. Phys. 82, 4286 (1997).CrossRefGoogle Scholar