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Annealing Effects on Electrical Properties and Defects of CaCu3Ti4O12 Thin Films Deposited by Pulsed Laser Deposition

Published online by Cambridge University Press:  01 February 2011

Guochu Deng  and
Paul Muralt
Guochu Deng
Affiliation:
Guochu.Deng@psi.ch, Paul Scherrer Institute, Villingen, Switzerland
Paul Muralt
Affiliation:
paul.muralt@epfl.ch, EPFL, Materials, Station 12, Ceramics Lab, Lausanne, 1015, Switzerland
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Abstract

We present a systematic study of semiconductor and dielectric properties as a function of annealing treatments at CCTO thin films deposited by pulsed laser deposition at 720 °C in 200 mTorr oxygen. The as-deposited thin film samples contain a high concentration of defects that contribute to the semiconductivity in the interior of grains. With increasing annealing temperature, the apparent dielectric constant decreases, and the resistance increases, both at a given temperature (e.g. room temperature). After annealing at 680oC, the semiconductivity was almost completely suppressed and CaCu3Ti4O12 behaved as a dielectric material. Knowing that oxygen vacancies are removed during annealing, one can infer that the dopant states are related to oxygen vacancies. A double plateau behavior in the dielectric constant vs temperature graph indicates that there are at least two defect levels in CaCu3Ti4O12 thin films. This was confirmed by simulating the capacitance response of a Schottky barrier containing two defect levels. Apart of the usual acceptor level, a trap at 500 meV from the valence band was identified. The finally achieved quasi intrinsic material exhibits a negative temperature dependency of the dielectric constant below 120 K.

Keywords

dielectric propertiessemiconductingthin film
Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 1256: Symposium N – Functional Oxide Nanostructures and Heterostructures , 2010 , 1256-N02-06
Copyright
Copyright © Materials Research Society 2010

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References

1 Ramirez, A. P., Subramanian, M. A., Gardel, M., Blumberg, G., Li, D., Vogt, T., and Shapiro, S. M., Solid State Commun. 115, 217–220 (2000).Google Scholar
2 Homes, C. C., Vogt, T., Shapiro, S. M., Wakimoto, S., and Ramirez, A. P., Science 293, 673 (2001).Google Scholar
3 Sinclair, D. C., Adams, T. B., Morrison, F. D., and West, A. R., Appl. Phys. Lett. 80, 2153–2155 (2002).Google Scholar
4 Si, W., Cruz, E. M., Johnson, P. D., Barnes, P. W., Woodward, P., and Ramirez, A. P., Appl. Phys. Lett. 81, 2056–2058 (2002).Google Scholar
5 Deng, G., Xanthopoulos, N., and Muralt, P., Appl. Phys. Lett. 92, 172909 (2008).Google Scholar
6 Ferrarelli, M. C., Adams, T. B., Feteira, A., Sinclair, D. C., and West, A. R., Appl. Phys. Lett. 89, 212904 (2006).Google Scholar
7 Liu, Y., Withers, R. L., and Wei, X., Phys. Rev. B 72, 2, 134104 (2005).Google Scholar
8 Subramanian, M. A. and Sleight, A. W., Solid State Sci. 4, 347–351 (2002).Google Scholar
9 Deng, G., Yamada, T., and Muralt, P., Appl. Phys. Lett. 91, 202903 (2007).Google Scholar
10 Maeder, T., Sagalowicz, L., and Muralt, P., Jpn. J. Appl. Phys. 37,2007–2012 (1998).Google Scholar
11 Deng, G., Yamada, T., and Muralt, P., MRS Proceedings 2008 Spring, 1073 1073-H05 H05-04 (2008).Google Scholar
12 Deng, G., and Muralt, P., Phys. Rev. B 81, 224111 (2010).Google Scholar
13 Ramireza, A. P., Subramanian, M. A., Gardela, M., Blumberga, G., Lib, D., Vogtc, T., and Shapiroc, S. M., Solid State Commun. 115, 217–220 (2000).Google Scholar
14 Deng, G., He, Z., and Muralt, P., J. Appl. Phys. 105, 084106 (2009).Google Scholar
15 Hao, J., Si, W., Xi, X. X., Guo, R., Bhalla, A. S., and Cross, L. E., Appl. Phys. Lett. 76, 3100–3102 (2000).Google Scholar
16 Vincent, G., Bois, D., and Pinard, P., J Appl. Phys. 46, 5173 (1975).Google Scholar
17 Ferrarelli, M. C., Nuzhnyy, D., DSinclair, D.C., Kamba, S., Phys. Rev. B 81 , 224112 (2010).Google Scholar
18 Sinclair, D.C., Adams, T.B., Morrison, F.D., West, A.R., Appl. Phys. Lett. 80, 2153–2155 (2002).Google Scholar