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Piezoelectric and dielectric tunabilities of ultra-thin ferroelectric heterostructures

Published online by Cambridge University Press:  01 June 2006

S. Zhong
Affiliation:
Department of Materials Science andEngineering and Institute of Materials Science, University of Connecticut, Storrs, Connecticut 06269
S.P. Alpay*
Affiliation:
Department of Materials Science andEngineering and Institute of Materials Science, University of Connecticut, Storrs, Connecticut 06269
V. Nagarajan
Affiliation:
School of Materials Science and Engineering, University of New South Wales, Sydney NSW 2052, Australia
*
a) Address all correspondence to this author. e-mail: [email protected]
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Abstract

The scaling of the piezoelectric and dielectric constants with film thickness in ultra-thin ferroelectric heterostructures is investigated. Epitaxial (001) PbZr0.2Ti0.8O3 films ranging in thickness from 5 nm to 30 nm with top and bottom SrRuO3 electrodes were grown onto (001) SrTiO3 substrates via pulsed laser deposition. Piezoelectric and dielectric measurements were performed using an atomic force microscope. The remnant value of the out of plane piezoresponse (d33) decreases from 60 pm/V for the 30 nm film to just 7 pm/V for the 5 nm film. This systematic decline in d33 is accompanied by a corresponding increase in the coercive field. The d33 loops show a systematic increase in tilt towards the applied field axis as function of reducing thickness coupled with a decrease in piezoelectric tunability. The small-signal relative dielectric response in the direction normal to the film-substrate interface decreases from 140 for a 50 nm film to just 60 for a 8 nm film. A similar drop is also observed in the dielectric tunability, from ∼17% to approximately −2% at an electric field of 750 kV/cm with the film thickness decreasing from 50 nm to 8 nm. We show that these observations cannot be explained using a straightforward application of a modified Landau-Devonshire thermodynamic model that incorporates the internal stresses due to the lattice and thermal expansion mismatch between the film and the substrate. We attribute this behavior to degradation in the polarization due to an intrinsic finite size effect.

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Articles
Copyright
Copyright © Materials Research Society 2006

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References

REFERENCES

1.Ahn, C.H., Rabe, K.M., Triscone, J.M.: Ferroelectricity at the nanoscale: Local polarization in oxide thin films and heterostructures. Science 303, 488 (2004).CrossRefGoogle ScholarPubMed
2.Akdogan, E.K., Safari, A.: Phenomenological theory of size effects on the cubic-tetragonal phase transition in BaTiO3 nanocrystals. Jpn. J. Appl. Phys. 41, 7170 (2002).CrossRefGoogle Scholar
3.Fong, D.D., Stephenson, G.B., Streiffer, S.K., Eastman, J.A., Auciello, O., Fuoss, P.H., Thompson, C.: Ferroelectricity in ultrathin perovskite films. Science 304, 1650 (2004).CrossRefGoogle ScholarPubMed
4.Lichtensteiger, C., Triscone, J.M., Junquera, J., Ghosez, P.: Ferroelectricity and tetragonality in ultrathin PbTiO3 films. Phys. Rev. Lett. 94, 047603 (2005).CrossRefGoogle ScholarPubMed
5.Akdogan, E.K., Rawn, C.J., Porter, W.D., Payzant, E.A., Safari, A.: Size effects in PbTiO3 nanocrystals: Effect of particle size on spontaneous polarization and strains. J. Appl. Phys. 97, 084305 (2005).Google Scholar
6.Bune, A.V., Fridkin, V.M., Ducharme, S., Blinov, L.M., Palto, S.P., Sorokin, A.V., Yudin, S.G., Zlatkin, A.: Two-dimensional ferroelectric films. Nature 391, 874 (1998).Google Scholar
7.Kim, Y.S., Kim, D.H., Kim, J.D., Chang, Y.J., Noh, T.W., Kong, J.H., Char, K., Park, Y.D., Bu, S.D., Yoon, J.G., Chung, J.S.: Critical thickness of ultrathin ferroelectric BaTiO3 films. Appl. Phys. Lett. 86, 102907 (2005).CrossRefGoogle Scholar
8.Yanase, N., Abe, K., Fukushima, N., Kawakubo, T.: Thickness dependence of ferroelectricity in heteroepitaxial BaTiO3 thin film capacitors. Jpn. J. Appl. Phys. 38, 5305 (1999).CrossRefGoogle Scholar
9.Fujisawa, H., Shimizu, M., Niu, H., Nonomura, H., Honda, K.: Ferroelectricity and local currents in epitaxial 5- and 9-nm-thick Pb(Zr,Ti)O3 ultrathin films by scanning-probe microscopy. Appl. Phys. Lett. 86, 012903 (2005).Google Scholar
10.Tybell, T., Ahn, C.H., Triscone, J.M.: Ferroelectricity in thin perovskite films. Appl. Phys. Lett. 75, 856 (2005).Google Scholar
11.Zhong, W.L., Qu, B.D., Zhang, P.L., Wang, Y.G.: Thickness dependence of the dielectric susceptibility of ferroelectric thin films. Phys. Rev. B 50, 12375 (1994).Google Scholar
12.Ghosez, P., Rabe, K.M.: Microscopic model of ferroelectricity in stress-free PbTiO3 ultrathin films. Appl. Phys. Lett. 76, 2767 (2000).Google Scholar
13.Glinchuk, M.D., Eliseev, E.A., Stephanovich, V.A.: The depolarization field effect on the thin ferroelectric films properties. Physica B (Amsterdam) 322, 356 (2002).Google Scholar
14.Zembilgotov, A.G., Pertsev, N.A., Kohlstedt, H., Waser, R.: Ultrathin epitaxial ferroelectric films grown on compressive substrates: Competition between the surface and strain effects. J. Appl. Phys. 91, 2247 (2002).Google Scholar
15.Junquera, J., Ghosez, P.: Critical thickness for ferroelectricity in perovskite ultrathin films. Nature 422, 506 (2003).Google Scholar
16.Stachiotti, M.G.: Ferroelectricity in BaTiO3 nanoscopic structures. Appl. Phys. Lett. 84, 251 (2004).Google Scholar
17.Zhuravlev, M.Y., Sabirianov, R.F., Jaswal, S.S., Tsymbal, E.Y.: Giant electroresistance in ferroelectric tunnel junctions. Phys. Rev. Lett. 94, 246802 (2005).CrossRefGoogle Scholar
18.Bune, A.V., Ducharme, S., Fridkin, V.M., Binov, L., Palto, S.P., Petukhova, N., Yudin, S.G.: Novel switching phenomena in ferroelectric Langmuir-Blodgett films. Appl. Phys. Lett. 67, 3975 (1995).CrossRefGoogle Scholar
19.Contreras, J.R., Kohlstedt, H., Poppe, U., Waser, R., Buchal, C., Pertsev, N.A.: Resistive switching in metal-ferroelectric-metal junctions. Appl. Phys. Lett. 83, 4595 (2003).CrossRefGoogle Scholar
20.Qu, H., Yao, W., Garcia, T., Zhang, J., Sorokin, A.V., Ducharme, S., Dowben, P.A., Fridkin, V.M.: Nanoscale polarization manipulation and conductance switching in ultrathin films of a ferroelectric copolymer. Appl. Phys. Lett. 82, 4322 (2003).Google Scholar
21.Basceri, C., Streiffer, S.K., Kingon, A.I., Waser, R.: The dielectric response as a function of temperature and film thickness of fiber-textured (Ba,Sr)TiO3 thin films grown by chemical vapor deposition. J. Appl. Phys. 82, 2497 (1997).Google Scholar
22.Ban, Z.G., Alpay, S.P.: Phase diagrams and dielectric response of epitaxial barium strontium titanate films: A theoretical analysis. J. Appl. Phys. 91, 9288 (2002).CrossRefGoogle Scholar
23.Alpay, S.P., Misirlioglu, I.B., Nagarajan, V., Ramesh, R.: Can interface dislocations degrade ferroelectric properties? Appl. Phys. Lett. 85, 2044 (2004).CrossRefGoogle Scholar
24.Nagarajan, V., Prasertchoung, S., Zhao, T., Zheng, H., Ouyang, J., Ramesh, R., Tian, W., Pan, X.Q., Kim, D.M., Eom, C.B., Kohlstedt, H., Waser, R.: Size effects in ultrathin epitaxial ferroelectric heterostructures. Appl. Phys. Lett. 84, 5225 (2004).CrossRefGoogle Scholar
25.Christman, J.A., Woolcott, R.R. Jr., Kingon, A.I., Nemanich, R.J.: Piezoelectric measurements with atomic force microscopy. Appl. Phys. Lett. 73, 3851 (1998).Google Scholar
26.Nagarajan, V., Stanishevsky, A., Chen, L., Zhao, T., Liu, B.T., Melngailis, J., Roytburd, A.L., Ramesh, R., Finder, J., Yu, Z., Droopad, R., Eisenbeiser, K.: Realizing intrinsic piezoresponse in epitaxial submicron lead zirconate titanate capacitors on Si. Appl. Phys. Lett. 81, 4215 (2002).CrossRefGoogle Scholar
27.Shao, R., Kalinin, S.V., Bonnell, D.A.: Local impedance imaging and spectroscopy of polycrystalline ZnO using contact atomic force microscopy. Appl. Phys. Lett. 82, 1869 (2003).CrossRefGoogle Scholar
28.Dawber, M., Chandra, P., Littlewood, P.B., Scott, J.F.: Depolarization corrections to the coercive field in thin-film ferroelectrics. J. Phys. Condens. Matter. 15, L393 (2003).Google Scholar
29.Chen, L., Nagarajan, V., Ramesh, R., Roytburd, A.L.: Nonlinear electric field dependence of piezoresponse in epitaxial ferroelectric lead zirconate titanate thin films. J. Appl. Phys. 94, 5147 (2003).Google Scholar
30.Vendik, O.G., Hollmann, E.K., Kozyrev, A.B., Prudan, A.M.: Ferroelectric tuning of planar and bulk microwave devices. Journal of Superconductivity 12, 325 (1999).CrossRefGoogle Scholar
31.Tagantsev, A.K., Sherman, V.O., Astafiev, K.F., Venkatech, J., Setter, N.: Ferroelectric Materials for Microwave Tunable Applications. J. Electroceram. 11, 5 (2003).CrossRefGoogle Scholar
32.Ban, Z-G., Alpay, S.P.: Optimization of the tunability of barium strontium titanate films via epitaxial stresses. J. Appl. Phys. 93, 504 (2003).Google Scholar
33.Pertsev, N.A., Zembilgotov, A.G., Tagantsev, A.K.: Effect of mechanical boundary conditions on phase diagrams of epitaxial ferroelectric thin films. Phys. Rev. Lett. 80, 1988 (1998).CrossRefGoogle Scholar
34.Hellwege, K-H., Hellwege, A.M.: Landolt-Bornstein, Numerical Data and Functional Relationships in Science and Technology Vol. 16 (Springler, Berlin, 1981).Google Scholar
35.Speck, J.S., Pompe, W.: Domain configurations due to multiple misfit relaxation mechanisms in epitaxial ferroelectric thin films.1. Theory. J. Appl. Phys. 76, 466 (1994).CrossRefGoogle Scholar
36.Alpay, S.P., Roytburd, A.L.: Thermodynamics of polydomain heterostructures. III. Domain stability map. J. Appl. Phys. 83, 4714 (1998).Google Scholar
37. Thermodynamic, elastic, and electrostrictive parameters: TC = 459.1 °C, C = 1.642 × 105 °C, b = 3.05 × 107 m5/C2F, c = 2.475 × 108 m9/C4F, Q 12 = −2.446 × 10−2 m4/C2, S = 6 × 10−12 m2/N, ξ = 1.3.Google Scholar
38.Matthews, J.W., Blakeslee, A.E.: Defects in epitaxial multilayers: I. Misfit dislocations. J. Cryst. Growth 27, 118 (1974).Google Scholar
39.Streiffer, S.K., Basceri, C., Parker, C.B., Lash, S.E., Kingon, A.I.: Ferroelectricity in thin films: The dielectric response of fiber-textured (BaxSr1-x)Ti1+yO3+z thin films grown by chemical vapor deposition. J. Appl. Phys. 86, 4565 (1999).CrossRefGoogle Scholar
40.Tagantsev, A.K., Landivar, M., Colla, E., Setter, N.: Identification of passive layer in ferroelectric thin films from their switching parameters. J. Appl. Phys. 78, 2623 (1995).CrossRefGoogle Scholar
41.Kretschmer, R., Binder, K.: Surface effects on phase transitions in ferroelectrics and dipole magnets. Phys. Rev. B 20, 1065 (1979).CrossRefGoogle Scholar
42.Tilley, D.R., Zeks, B.: Landau theory of phase transitions in thick films. Solid State Commun. 49, 823 (1984).CrossRefGoogle Scholar
43.Zhong, W.L., Wang, Y.G., Zhang, P.L., Qu, B.D.: Phenomenological study of the size effect on phase transitions in ferroelectric particles. Phys. Rev. B 50, 698 (1994).Google Scholar
44.Jiang, B., Bursill, L.A.: Phenomenological theory of size effects in ultrafine ferroelectric particles of lead titanate. Phys. Rev. B 60, 9978 (1999).CrossRefGoogle Scholar
45.Zhang, J., Yin, Z., Zhang, M-S., Scott, J.F.: Size-driven phase transition in stress-induced ferroelectric thin films. Solid State Commun. 118, 241 (2001).CrossRefGoogle Scholar
46.Ban, Z.G., Alpay, S.P., Mantese, J.V.: Fundamentals of graded ferroic materials and devices. Phys. Rev. B 67, 184104 (2003).Google Scholar