Hostname: page-component-586b7cd67f-2brh9 Total loading time: 0 Render date: 2024-11-24T17:38:57.450Z Has data issue: false hasContentIssue false

Oxygen Content And Crystallinity Effects in Pulsed Laser Deposited Lanthanum Manganite Thin Films

Published online by Cambridge University Press:  10 February 2011

Srinivas V. Pietambaram
Affiliation:
Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611-6400, U.S.A
D. Kumar
Affiliation:
Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611-6400, U.S.A
Rajiv K. Singh
Affiliation:
Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611-6400, U.S.A
C. B. Lee
Affiliation:
Department of Electrical Engineering, North Carolina A & T University, Greensboro, North Carolina 27411, U.S.A
Get access

Abstract

Eventhough colossal magnetoresistance in Lanthanum calcium manganite (LCMO) thin films was known for a long time, the effect of oxygen content and crystallinity on the properties of these films is not clearly understood. It is in this context that we have performed a systematic study of these effects by annealing the films in various ambients. A series of LCMO thin films have been grown in situ on (100) LaAlO3 substrates using a pulsed laser deposition technique under identical conditions. Microstructural characterization carried out on these films has shown that the films are smooth, single phase and highly textured. The films were subjected to the following post deposition treatments: (i) annealing in oxygen at 900°C for 4 hrs, (ii) annealing in argon at 900°C for 4 hrs, (iii) annealing in oxygen at 500°C for 12 hrs, (iv) annealing in argon for 12 hrs and (v) annealing in vacuum at 850°C for half-an-hour. As deposited LCMO films show a transition temperature of 260 K and a magnetoresistance ratio (defined as [R(0)−R(H)/R(H)]) of 190% at 260 K in 5T magnetic field. The samples subjected to 500°C oxygen and Ar anneal have shown no change in the transition temperature and MR ratio. The films subjected to a 900°C annealing in Ar ambient have shown marginal improvement in transition temperature but a drastic improvement in the MR ratio (525%). 900°C oxygen annealed films have shown an improvement in the transition temperature (290 K) and MR ratio (225%) over as deposited films. Vacuum annealed samples have shown deteriorated properties. These results indicate that the metal-insulator transition is related to the oxygen content of the films while the MR ratio is related to the domain size.

Type
Research Article
Copyright
Copyright © Materials Research Society 2000

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1 Searle, C. W. and Wang, S. T., Can. J. Phys. 48, 2023 (1970).Google Scholar
2 Helmolt, R. Von, Wecker, J., Holzapfel, B., Schultz, L., and Samwer, K., Phys. Rev. Lett. 71, 2331 (1993).Google Scholar
3 Jin, S., Tiefel, T. H., McCormack, M., Fastnatch, R.A., Ramesh, R., and Chen, L. H., Science 264, 413 (1994).Google Scholar
4 Xiong, G. C., Li, Qi, Ju, H. L., Greene, R. L., and Venkatesan, T., AppI. Phys. Lett. 66, 1689 (1995).Google Scholar
5 Wei, Z., Boyd, W., Elliot, M., and Herrenden-Harkerand, W., Appl. Phvs. Lett. 69, 3926 (1996).Google Scholar
6 Ju, H. L., Gopalakrishnan, J., Peng, J. L., Li, Qi, Xiong, G. C., Venkatesan, T. and Greene, R. L., Phys. Rev. B 51, 6143 Google Scholar
7 Mitchell, J. F., Argyriou, D. D., Potter, C. D., Hinks, D. G., Jorgensen, J. D., and Barder, S. D., Phys. Rev. B 54, 6172 (1996).Google Scholar
8 Prellier, W., Rajeswari, M., Venkatesan, T., and Greene, R. L., Appl. Phys. Lett. 75, 1446 (1999).Google Scholar
9 Matsumoto, Y., Hombo, j., Yamaguchi, Y., Nishida, M., and Chiba, A., Appl. Phys. Lett. 56, 1585 (1990).Google Scholar
10 Singh, R. K., Bhattacharya, D., Tiwari, P., Narayan, J., and Lee, C. B., Appl. Phys. Lett. 60, 255 (1992).Google Scholar
11 Pietambaram, Srinivas V., Kumar, D., Singh, Rajiv K., and Lee, C. B., Phys. Rev. B 58, 8182 (1998).Google Scholar
12 Zener, C., Phys. Rev. 82, 403 (1951).Google Scholar
13 Hwang, H. W., Palstra, T. T. M., Cheong, S.-W., and Batlogg, B., Phys. Rev B 52, 15046 (1995).Google Scholar
14 Moritomo, Y., Asamitsu, A., and Tokura, Y., Phys. Rev. B 51, 16491 (1995).Google Scholar
15 Urushibara, A., Moritomo, Y., Arima, T., Asamitsu, A., Kido, G., and Tokura, Y., Phys. Rev. B 51, 14103 (1995).Google Scholar
16 Schiffer, P., Ramirez, A. P., Bao, W., and Cheong, S.-W., Phys. Rev. Lett. 75, 3336 (1995).Google Scholar
17 Sun, J. R., Yeung, C. F., Zhao, K., Zhou, L. Z., Leung, C. H., Wong, H. K., and Shen, B. G., Appl. Phys. Lett. 76, 1164 (2000).Google Scholar