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Microstructures and electrical properties of CaCu3Ti4O12 thin films on Pt/TiO2/SiO2/Si substrates by pulsed laser deposition

Published online by Cambridge University Press:  26 August 2011

Sung-Yun Lee
Affiliation:
Department of Materials Science and Engineering, Research Institute of Advanced Materials (RIAM), Seoul National University, Seoul 151-744, Korea
Soon-Mi Choi
Affiliation:
Department of Materials Science and Engineering, Research Institute of Advanced Materials (RIAM), Seoul National University, Seoul 151-744, Korea
Mi-Young Kim
Affiliation:
Department of Materials Science and Engineering, Research Institute of Advanced Materials (RIAM), Seoul National University, Seoul 151-744, Korea
Sang-Im Yoo*
Affiliation:
Department of Materials Science and Engineering, Research Institute of Advanced Materials (RIAM), Seoul National University, Seoul 151-744, Korea
Ji Hye Lee
Affiliation:
Department of Physics, Ewha Womans University, Seoul 120-750, Korea
William Jo*
Affiliation:
Department of Physics, Ewha Womans University, Seoul 120-750, Korea
Young-Hwan Kim
Affiliation:
Nano-Materials Center, Korea Institute of Science and Technology, Seoul 136-791, Korea
Kyoung Jin Choi
Affiliation:
Nano-Materials Center, Korea Institute of Science and Technology, Seoul 136-791, Korea
*
a)Address all correspondence to these authors. e-mail: siyoo@snu.ac.kr
b)e-mail: wmjo@ewha.ac.kr
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Abstract

We investigated microstructures, compositional distributions, and electrical properties of dielectric CaCu3Ti4O12 (CCTO) thin films deposited on Pt/TiO2/SiO2/Si substrates from 700 to 800 °C by pulsed laser deposition. With increasing the deposition temperature from 700 to 750 °C, the dielectric constants (εr) of CCTO films were greatly enhanced from ∼300 to ∼2000 at 10 kHz, respectively. However, the εr values of CCTO films were gradually decreased above 750 °C, which was surely attributable to the formation of a TiO2-rich dead layer at the interface between CCTO and Pt electrode. Compositional analyses by Auger electron spectroscopy, energy dispersive spectroscopy, and electron energy loss spectroscopy revealed that the TiO2-rich dead layer became thicker because of severe Cu diffusion from CCTO films to Pt electrode. The leakage current behaviors of CCTO films are in good agreement with Poole–Frenkel conduction mechanism, where both the TiO2-rich dead layer and rutile TiO2 nanocrystalline particles are considered to play a role of charge trapping centers.

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Articles
Copyright
Copyright © Materials Research Society 2011

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References

REFERENCES

1.Subramanian, M.A., Li, D., Duan, N., Reisner, B.A., and Sleight, A.W. : High dielectric constant in ACu3Ti4O12 and ACu3Ti3FeO12 phases. J. Solid State Chem. 151, 323 (2000).CrossRefGoogle Scholar
2.Chung, S.Y., Kim, I.D., and Kang, S.J.L. : Strong nonlinear current–voltage behaviour in perovskite-derivative calcium copper titanate. Nat. Mater. 3, 774 (2004).CrossRefGoogle ScholarPubMed
3.Sinclair, D.C., Adams, T.B., Morrison, F.D., and West, A.R. : CaCu3Ti4O12: One-step internal barrier layer capacitor. Appl. Phys. Lett. 80, 2153 (2002).CrossRefGoogle Scholar
4.Adams, T.B., Sinclair, D.C., and West, A.R. : Giant barrier layer capacitance effects in CaCu3Ti4O12 ceramics. Adv. Mater. 14, 1321 (2002).3.0.CO;2-P>CrossRefGoogle Scholar
5.Lin, Y.H., Cai, J., Li, M., Nan, C.W., and He, J. : Grain boundary behavior in varistor-capacitor TiO2-rich CaCu3Ti4O12 ceramics. J. Appl. Phys. 103, 074111 (2008).Google Scholar
6.Adams, T.B., Sinclair, D.C., and West, A.R. : Influence of processing conditions on the electrical properties of CaCu3Ti4O12 ceramics. J. Am. Ceram. Soc. 89, 3129 (2006).Google Scholar
7.Fang, L., Shen, M., and Yao, D. : Microstructure and dielectric properties of pulsed-laser-deposited CaCu3Ti4O12 thin films on LaNiO3 buffered Pt /Ti /SiO2/Si substrates. Appl. Phys. A 80, 1763 (2005).Google Scholar
8.Li, Y.W., Hu, Z.G., Sun, J.L., Meng, X.J., and Chu, J.H. : Effects of LaNiO3 bottom electrode on structural and dielectric properties of CaCu3Ti4O12 films fabricated by sol-gel method. Appl. Phys. Lett. 92, 042901 (2008).Google Scholar
9.Homes, C.C., Vogt, T., Shapiro, S.M., Wakimoto, S., and Ramirez, A.P. : Perovskite-related oxide optical response of high-dielectric-constant. Science 293, 673 (2001).Google Scholar
10.Li, J., Sleight, A.W., and Subramanian, M.A. : Evidence for internal resistive barriers in a crystal of the giant dielectric-constant material: CaCu3Ti4O12. Solid State Commun. 135, 260 (2005).Google Scholar
11.Fang, T.T. and Liu, C.P. : Evidence of the internal domains for inducing the anomalously high dielectric constant of CaCu3Ti4O12. Chem. Mater. 17, 5167 (2005).CrossRefGoogle Scholar
12.Ramirez, M.A., Bueno, P.R., Tararam, R., Cavlheiro, A.A., Longo, E., and Varela, J.A. : Evaluation of the effect of the stoichiometric ratio of Ca/Cu on the electrical and microstructural properties of the CaCu3Ti4O12 polycrystalline system. J. Phys. D Appl. Phys. 42, 185503 (2009).Google Scholar
13.Krohns, S., Lunkenheimer, P., Ebbinghaus, S.G., and Loidl, A. : Broadband dielectric spectroscopy on single-crystalline and ceramic CaCu3Ti4O12. Appl. Phys. Lett. 91, 022910 (2007).Google Scholar
14.Whangbo, M.H. and Subramanian, M.A. : Structural model of planar defects in CaCu3Ti4O12 exhibiting a giant dielectric constant. Chem. Mater. 18, 3257 (2009).Google Scholar
15.Ferrarelli, M.C., Sinclair, D.C., West, A.R., Dabkowska, H.A., Dabkowski, A., and Luke, G.M. : Comment on the origin(s) of the giant permittivity effect in CaCu3Ti4O12 single crystals and ceramics. J. Mater. Chem. 19, 5916 (2009).CrossRefGoogle Scholar
16.Si, W., Cruz, E.M., Johnson, P.D., Barnes, P.W., Woodward, P., and Ramirez, A.P. : Epitaxial thin films of the giant-dielectric-constant material CaCu3Ti4O12 grown by pulsed laser deposition. Appl. Phys. Lett. 81, 2056 (2002).CrossRefGoogle Scholar
17.Lin, Y., Chen, Y.B., Garret, T., Liu, S.W., Chen, L., Bontchev, R.P., Jacobson, A., Jiang, J.C., Meletis, E.I., Horwitz, J., and Wu, H.D. : Epitaxial growth of dielectric CaCu3Ti4O12 thin films on (001) LaAlO3 by pulsed laser deposition. Appl. Phys. Lett. 81, 631 (2002).CrossRefGoogle Scholar
18.Fang, L. and Shen, M. : Deposition and dielectric properties of CaCu3Ti4O12 thin films on Pt/Ti/SiO2/Si substrates using pulsed laser deposition. Thin Solid Films 440, 60 (2003).Google Scholar
19.Fang, L., Shen, M., and Cao, W. : Effects of postanneal conditions on the dielectric properties of CaCu3Ti4O12 thin films prepared on Pt/Ti/SiO2/Si substrates. J. Appl. Phys. 95, 6483 (2004).CrossRefGoogle Scholar
20.Deng, G., Yamada, T., and Muralt, P. : Evidence for the existence of a metal-insulator-semiconductor junction at the electrode interfaces of CaCu3Ti4O12 thin film capacitors. Appl. Phys. Lett. 91, 202903 (2007).CrossRefGoogle Scholar
21.Zhao, Y.L., Pan, G.W., Ren, Q.B., Cao, Y.G., Feng, L.X., and Jiao, Z.K. : High-dielectric constant in CaCu3Ti4O12 thin film prepared by pulsed laser deposition. Thin Solid Films 445, 7 (2003).CrossRefGoogle Scholar
22.Deng, G., Xanthopoulos, N., and Muralt, P. : Chemical nature of colossal dielectric constant of CaCu3Ti4O12 thin film by pulsed laser deposition. Appl. Phys. Lett. 92, 172909 (2008).Google Scholar
23.Mitsugi, M., Asanuma, S., Uesu, Y., Fukunaga, M., Kobayashi, W., and Terasaki, I. : Origin of colossal dielectric response of CaCu3Ti4O12 studied by using CaTiO3 /CaCu3Ti4O12/CaTiO3 multilayer thin films. Appl. Phys. Lett. 90, 242904 (2007).Google Scholar
24.Fang, L., Shen, M., Yang, J., and Li, Z. : Reduced dielectric loss and leakage current in CaCu3Ti4O12/SiO2/CaCu3Ti4O12 multilayered films. Solid State Commun. 137, 381 (2006).Google Scholar
25.Lee, S.Y., Kim, Y.H., Choi, K.J., Jung, S.M., and Yoo, S.I. : Effect of copper-oxide segregation on the dielectric properties of CaCu3Ti4O12 thin films fabricated by pulsed laser deposition. Thin Solid Films 518, 5711 (2010).Google Scholar
26.Deng, G., He, Z., and Muralt, P. : Physical aspects of colossal dielectric-constant material CaCu3Ti4O12 thin films. J. Appl. Phys. 105, 084106 (2009).Google Scholar
27.Fang, L., Shen, M., and Li, Z. : Effect of double-sided CaTiO3 buffer layers on the electrical properties of CaCu3Ti4O12 films on Pt/Ti/SiO2 /Si substrates. J. Appl. Phys. 100, 104101 (2006).CrossRefGoogle Scholar
28.Fang, L. and Shen, M. : Effect of laser fluence on the microstructure and dielectric properties of pulsed laser-deposited CaCu3Ti4O12 thin films. J. Cryst. Growth 310, 3470 (2008).Google Scholar
29.Maurya, D., Singh, D.P., Agrawal, D.C., and Mohapatra, Y.N. : Preparation of high-dielectric constant thin films of CaCu3Ti4O12 by sol–gel. Bull. Mater. Sci. 31, 55 (2008).CrossRefGoogle Scholar
30.Jimenez, R., Calzada, M.L., Bretos, I., Goes, J.C., and Sombra, A.S.B. : Dielectric properties of sol–gel derived CaCu3Ti4O12 thin films onto Pt/TiO2/Si(1 0 0) substrates. J. Eur. Ceram. Soc. 27, 3829 (2007).Google Scholar
31.Li, Y.W., Hu, Z.G., Sun, J.L., Meng, X.J., and Chu, J.H. : Preparation and properties of CaCu3Ti4O12 thin film grown on LaNiO3-coated silicon by sol–gel process. J. Cryst. Growth 310, 378 (2008).Google Scholar
32.Chang, L.C., Lee, D.Y., Ho, C.C., and Chiou, B.S. : Thickness-dependent microstructures and electrical properties of CaCu3Ti4O12 films derived from sol–gel process. Thin Solid Films 516, 454 (2007).Google Scholar
33.Singh, D.P., Mohapatra, Y.N., and Agrawal, D.C. : Dielectric and leakage current properties of sol–gel derived calcium copper titanate (CCTO) thin films and CCTO/ZrO2 multilayers. Mater. Sci. Eng., B 157, 58 (2009).Google Scholar
34.Joanni, E., Savu, R., Bruno, P.R., Longo, E., and Varela, J.A. : P-type semiconducting gas sensing behavior of nanoporous rf sputtered CaCu3Ti4O12 thin films. Appl. Phys. Lett. 92, 132110 (2008).Google Scholar
35.Lin, S.Y., Chen, Y.C., Wang, C.M., Kao, K.S., and Chan, C.Y. : Effect of rapid thermal annealing on sputtered CaCu3Ti4O12 thin films. J. Electron. Mater. 38, 453 (2009).Google Scholar
36.Prakash, B.S., Varma, K.B.R., Michau, D., and Maglione, M. : Deposition and dielectric properties of CaCu3Ti4O12 thin films deposited on Pt/Ti/SiO2/Si substrates using radio frequency magnetron sputtering. Thin Solid Films 516, 2874 (2008).CrossRefGoogle Scholar
37.Nigro, R.L., Toro, R.G., Malandrino, G., Fragala, I.L., Fiorenza, P., and Raineri, V. : Chemical stability of CaCu3Ti4O12 thin films grown by MOCVD on different substrates. Thin Solid Films 515, 6470 (2007).CrossRefGoogle Scholar
38.Nigro, R.L., Toro, R.G., Malandrino, G., Fragala, I.L., Fiorenza, P., and Raineri, V. : Effects of high temperature annealing on MOCVD grown CaCu3Ti4O12 films on LaAlO3 substrates. Surf. Coat. Technol. 201, 9243 (2007).Google Scholar
39.Lee, S.Y., Yoo, D.K., and Yoo, S.I. : Microstructures and dielectric properties of Cu deficient and excess CaCu3Ti4O12 polycrystalline ceramics. Electron. Mater. Lett. 3, 23 (2007).Google Scholar
40.Jung, W.W., Choi, S.K., Kweon, S.Y., and Yeom, S.J. : Platinum (100) hillock growth in Pt/Ti electrode stack for SrBi2Ta2O9 ferroelectric random access memory. J. Electroceram. 13, 55 (2004).Google Scholar
41.Chen, H., Yang, C., Fu, C., Zhang, J., Liao, J., and Hu, L. : Effects of interface on the dielectric properties of Ba0.6Sr0.4TiO3 thin film capacitors. Appl. Surf. Sci. 254, 3175 (2008).CrossRefGoogle Scholar
42.Wang, J., Zhang, T., Zhang, B., Jiang, J., Pan, R., and Ma, Z. : Interfacial characteristic of (Ba, Sr)TiO3 thin films deposited on different bottom electrodes. J. Mater. Sci.- Mater. Electron. 20, 1208 (2009).Google Scholar
43.Liao, J.X., Yang, C.R., Zhang, J.H., Fu, C.L., Chen, H.W., and Leng, W.J. : The interfacial structures of (Ba, Sr)TiO3 films deposited by radio frequency magnetron sputtering. Appl. Surf. Sci. 252, 7407 (2006).CrossRefGoogle Scholar
44.Zhao, C., Zhu, Q., Wu, D., and Li, A. : Composition-dependent electrical characteristics and interface microstructures of solution-derived Nd-substituted Bi4Ti3O12 thin films on Pt electrodes. J. Phys. D: Appl. Phys. 42, 185412 (2009).Google Scholar
45.Abazari, M., Akdogan, E.K., and Safari, A. : Dielectric and ferroelectric properties of strain-relieved epitaxial lead-free KNN-LT-LS ferroelectric thin films on SrTiO3 substrates. J. Appl. Phys. 103, 104106 (2008).CrossRefGoogle Scholar
46.Gonon, P. and Kamel, F.E.I. : Dielectric response of Cu/amorphous BaTiO3 /Cu capacitors. J. Appl. Phys. 101, 073901 (2007).CrossRefGoogle Scholar
47.Massalski, T.B., Okamoto, H., Subramanian, P.R., and Kacprzak, L. : Binary Alloy Phase Diagrams, 2nd, ed. (Orlando, FL: Alloy phase diagram international commission, 1986), Vol. 2 p.1461.Google Scholar
48.Vorobiev, A., Rundqvist, P., and Khamchane, K. : Microwave loss mechanisms in Ba0.25Sr0.75TiO3 thin film varactors. J. Appl. Phys. 96, 4642 (2004).CrossRefGoogle Scholar
49.Nigro, R.L., Malandrino, G., Toro, R.G., Losurdo, M., Bruno, G., and Fragala, I.L. : Recent advances in characterization of CaCu3Ti4O12 thin films by spectroscopic ellipsometric metrology. J. Am. Chem. Soc. 127, 13772 (2005).CrossRefGoogle ScholarPubMed
50.Fang, L., Shen, M., Yang, J., and Li, Z. : The effect of SiO2 barrier layer on the dielectric properties of CaCu3Ti4O12 films. J. Phys. D: Appl. Phys. 38, 4236 (2005).Google Scholar
51.Li, Y.W., Shen, Y.D., Hu, Z.G., Yue, F.Y., and Chu, J.H. : Effect of thickness on the dielectric property and nonlinear current-voltage behavior of CaCu3Ti4O12 thin films. Phys. Lett. A 373, 2389 (2009).Google Scholar
52.Vodungbo, B., Zheng, Y., Marangolo, M., Demaille, D., and Varalda, J. : Planar assembly of monodisperse metallic cobalt nanoparticles embedded in TiO2− δ matrix. J. Phys. Condens. Matter 19, 116205 (2007).Google Scholar
53.Mitterbauer, C., Kothleitner, G., and Hofer, F. : Comparative electron energy-loss near-edge fine structure investigations of titanium oxides. Microsc. Microanal. 9, 834 (2003).Google Scholar