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Influence of donor density in ZnO on ZnO–PrCoOx thin-film junctions: Role of O2 and Al dopant in varistors

Published online by Cambridge University Press:  03 March 2011

Yoshihiko Yano
Affiliation:
R&D Center, TDK Corporation, 2-15-7 Higashioowada, Ichikawa-shi, Chiba 272, Japan
Yukihiko Shirakawa
Affiliation:
R&D Center, TDK Corporation, 2-15-7 Higashioowada, Ichikawa-shi, Chiba 272, Japan
Hisao Morooka
Affiliation:
R&D Center, TDK Corporation, 2-15-7 Higashioowada, Ichikawa-shi, Chiba 272, Japan
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Abstract

ZnO/PrCoOx and ZnO/PrCoOx/ZnO junctions have been fabricated by sputtering as a model of a single grain boundary in a ceramic ZnO varistor. The relations between barrier parameters and varistor characteristics were investigated using voltage-current (V-I) capacitance-voltage (C-V), and deep-level transient spectroscopy (DLTS) measurements. The varistor voltage of the junctions increases as the donor density (ND) of the ZnO film decreases. The interface states vary according to the method of ZnO sputtering. A clear correlation has been established between the α value and the interface states. The highest α value is obtained when ND is ≃ 1018 cm−3, the interface level is 0.70 eV, and the breakdown voltage is 3–4 V. Oxygen is effective on control of ND in ZnO and the interface states. Al added as a dopant is also effective in terms of its ability to increase ND in ZnO. However, Al doping was found to degrade the interface states and increase the leakage current.

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Articles
Copyright
Copyright © Materials Research Society 1994

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References

REFERENCES

1Matuoka, M., Jpn. Appl. Phys. 10, 736 (1971).CrossRefGoogle Scholar
2Mukae, K., Tuda, K., and Nagasawa, I., Jpn. J. Appl. Phys. 16, 1361 (1977).CrossRefGoogle Scholar
3Levinson, L. M. and Philipp, H. R., J. Appl. Phys. 46, 1332 (1975).CrossRefGoogle Scholar
4Emtage, P. E., J. Appl. Phys. 48, 4372 (1977).CrossRefGoogle Scholar
5Einzinger, R., Appl. Surf. Sci. 3, 340 (1979).CrossRefGoogle Scholar
6Mahan, G. D., Levinson, L. M., and Philipp, H. R., J. Appl. Phys. 50, 2799 (1979).CrossRefGoogle Scholar
7Pike, G. E., Kurtz, S. R., Grourley, P. L., Philipp, H. R., and Levinson, L. M., J. Appl. Phys. 57, 5512 (1985).CrossRefGoogle Scholar
8Greuter, F., Blatter, G., Rossinelli, M., and Stucki, F., Advances in Varistor Technology (The American Ceramics Society, Westerville, OH, 1988), p. 31.Google Scholar
9Pike, G. E., in Grain Boundaries in Semiconductors, edited by Leamy, H. J., Pike, G. E., and Seager, C. H. (Mater. Res. Soc. Symp. Proc. 5, Elsevier Science Publishing, New York, 1982), p. 369.Google Scholar
10Blatter, G. and Greuter, F., Phys. Rev. B 33, 3952 (1986).Google Scholar
11Blatter, G. and Greuter, F., Phys. Rev. B 34, 8555 (1986).Google Scholar
12Lou, L. I., J. Appl. Phys. 50, 555 (1979).CrossRefGoogle Scholar
13Suzuoki, Y., Ohki, A., Mizutani, T., and Ieda, M., J. Phys. D 20, 511 (1987).CrossRefGoogle Scholar
14Yano, Y., Shirakawa, Y., and Morooka, H., J. Ceram. Soc. Jpn. 100, 547 (1992).Google Scholar
15Yano, Y., Shirakawa, Y., and Morooka, H., Jpn. J. Appl. Phys. 31, L1429 (1992).CrossRefGoogle Scholar
16Lang, D. V., J. Appl. Phys. 45, 3023 (1974).Google Scholar
17See, for example, Rhoderick, E. H. and Williams, R. H., Metal-Semiconductor Contacts (Oxford University Press, Oxford, 1988).Google Scholar
18Pike, G. E. and Seager, C. H., J. Appl. Phys. 50, 3414 (1979).CrossRefGoogle Scholar
19Tuda, K. and Mukae, K., IECEJ Tech. Rep. CPM86 29, 27 (1986).Google Scholar
20Stucki, F. and Greuter, F., Appl. Phys. Lett. 57, 446 (1990).CrossRefGoogle Scholar