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Plasma-Enhanced MOCVD of Superconducting Oxides

Published online by Cambridge University Press:  15 February 2011

Kenji Ebihara
Affiliation:
Department of Electrical Engineering and Computer Science, Kumamoto University, Kurokami, Kumamoto 860, Japan
Tomoyuki Fujishima
Affiliation:
Department of Electrical Engineering and Computer Science, Kumamoto University, Kurokami, Kumamoto 860, Japan
Masanobu Shiga
Affiliation:
Dojindo Laboratories, Kumamoto Techno Research Park, Kumamoto 861-23, Japan
Quanxi Jia
Affiliation:
Department of Electrical and Computer Engineering, State University of New York at Buffalo, Bonner Hall, Amherst, New York 14260
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Abstract

The plasma-enhanced MOCVD is developed to prepare high-Tc oxide superconducting thin films. Plasmas generated by microwave and rf discharges decompose effectively the source materials ( β-diketonate chelates) into their elements and oxides. YBaCuO thin films were deposited on the MgO substrate of 500–650 °C at total pressure of 0.6–5 Torr with O2 contents less than 30%. The as-grown films produced by two kinds of plasma enhancement were porous and consisted of crystalline grains, but showed the superconducting transition after heating procedure at around 800 °C. It is shown that the inherent crystalline orientations of the as-grown films determine the crystal structure of the post-annealed films. The film of the metal atomic ratios of 0.91 for Ba/Y and 2.64 for Cu/Y showed the superconducting properties with Tc(zero) of 89 K and the critical current density (at 77 K) of 5×104 A/cm2. Spectroscopic analysis showed that the plasmas are composed of many excited species such as Y, Y+, Ba, Ba+, Cu, YO, BaO, CuO. Formation of the metal-oxides through the gas phase reaction is essential for the high-quality YBaCuO superconducting thin film preparation in the PEMOCVD.

Type
Research Article
Copyright
Copyright © Materials Research Society 1994

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References

1. Bai, G. R., Tao, W., Wag, R. et al. , Appl. Phys. Lett., 55, 194 (1989).Google Scholar
2. Kobayashi, K., Ichikawa, S. and Okada, G., Jpn. J. Appl. Phys., 28, L2165 (1989).Google Scholar
3. Zhao, J., Noh, D. W., Chern, C. S., Li, Y. Q., Norris, P., Gallois, B. and Kear, B., Appl. Phys. Lett., 56, 2342 (1990).CrossRefGoogle Scholar
4. Chern, C. S., Zhao, J., Li, Y. Q., Norris, P., Kear, B. and Gallois, B., Appl. Phys. Lett., 57, 721 (1990).Google Scholar
5. Chern, C. S., Zhao, J., Li, Y. Q., Norris, P., Kear, B., Gallois, B. and Kalman, Z., Appl. Phys. Lett., 58, 185 (1991).Google Scholar
6. Li, Y. Q., Zhao, J., Chern, C. S., Lemonie, E. E., Gailois, B., Norris, P. and Kalman, Z., Appl. Phys. Lelt., 58, 2300 (1991).Google Scholar
7. Zhao, J., Chern, C. S., Li, Y. Q., Norris, P., Kear, B., Wu, X. D. and Muenchausen, R. E., Appl. Phys. Lett., 58, 2839(1991).CrossRefGoogle Scholar
8. Ebihara, K., Kanazawa, S., Ikegami, T. and Shiga, M., J. Appl. Phys., 68, 1151 (1990).Google Scholar
9. Ebihara, K., Ikegami, T., Kanazawa, S. and Shiga, M., Mat. Res. Soc. Symp. Proc. Plasma Processing and Synthesis of Materials III, Vol. 190,155 (1991).Google Scholar
10. Ebihara, K., Fujishima, T., Ikegami, T. and Shiga, M., IEEE Transactions on Applied Superconductivity, 3, 976 (1993).Google Scholar
11. Fujishima, T., Yoshimoto, Y. and Ebihara, K., Trans. IEEE of Japan(in Japanese), 113–A, 540 (1993).Google Scholar
12. Ebihara, K., Ikegami, T., Fujishima, T. and Shiga, M., Proceedings of 10th International Symposium on Plasma Chemistry, 3, 2.4-8p.1 (1991).Google Scholar
13. Fijii, K., Zama, H., and Oda, S., Jpn. J. Appl. Phys., 31, L787 (1992).Google Scholar
14. Ebihara, K., Yamagata, Y. and Ikegami, T., Proceedings of 1 1th International Symposium on Plasma Chemistry Vol. 4, 1615 (1993).Google Scholar
15. Fukumoto, M., Akasaka, Y., Shigehisa, T., Ikegami, T. and Ebihara, K., Proceedings of 6th Asia Conference on Electrical Discharge, (Oita, Japan, 1993) in press.Google Scholar
16. for example, International workshop on MOCVD of High Temperature Superconductors and Related Topics, (Organized by T. J. Marks, Evanston, Illinois, USA, 1992).Google Scholar