Hostname: page-component-586b7cd67f-r5fsc Total loading time: 0 Render date: 2024-11-25T17:25:42.232Z Has data issue: false hasContentIssue false
  • English
  • Français

Electronic Properties of ZnO Varistors: A New Model*

Published online by Cambridge University Press:  15 February 2011

G. E. Pike
G. E. Pike*
Affiliation:
Sandia National Laboratories, Albuquerque, New Mexico, 87185
Get access

Abstract

Much of the research on ZnO varistors has concentrated on the explanation of their dc current-voltage characteristics. However, varistors also have unusual ac properties which can be technologically important, and must be described by any comprehensive model. In an ideal varistor with identical grain boundaries throughout, there should be no dispersive capacitance at zero bias. In real varistors this capacitance varies considerably with frequency. This dispersion has two causes, charge trapping in the depletion regions and differing grain boundary barriers. Calculations for each process are given. For voltages well below the varistor breakdown value, the low frequency capacitance increases with applied voltage. At even higher voltages the capacitance turns over and becomes negative. All of these effects can be described with a double depletion layer/thermionic emission model. The anomalous capacitance behavior with bias is due to the modulation of the potential barriers by charge trapping at the grain boundaries. In the varistor breakdown regime minority carriers created by impact ionization are important.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 5: Symposium B – Grain Boundaries in Semiconductors , 1981 , 369
Copyright
Copyright © Materials Research Society 1982

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.)

Footnotes

*

This work performed at Sandia National Laboratories, supported by the U. S. Department of Energy under contract DE–AC04–76–DP00789.

References

REFERENCES

1. Mukae, K., Tsuda, K., and Nagasawa, I., Jap. J. Appl. Phys., 8, 1361 (1977).CrossRefGoogle Scholar
2. Bernasconi, J., Strassler, S., Knecht, B., Klein, H., and Menth, A.. Sol. St. Comm., 21, 867 (1977).CrossRefGoogle Scholar
3. Emtage, P. R., J. Appl. Phys., 48, 4372 (1977).CrossRefGoogle Scholar
4. Einzinger, R., Appl. Surface Sci., 1, 329 (1978).CrossRefGoogle Scholar
5. Eda, K., J. Appl. Phys., 49, 2964 (1978).CrossRefGoogle Scholar
6. Mahan, G. D., Levinson, L. M., and Philipp, H. R., J. Appl. Phys., 50, 2799 (1979).CrossRefGoogle Scholar
7. Hower, P. L. and Gupta, T. K., J. Appl. Phys., 50, 4847 (1979).CrossRefGoogle Scholar
8. Blackford, B. L., Rev. Sci. Instrum., 42, 1198 (1971).CrossRefGoogle Scholar
9. Seager, C. H. and Pike, G. E., Appl. Phys. Lett., 37, 747 (1980).Google Scholar
10. Matsuura, M. and Yamaoki, H., Jap. J. Appl. Phys., 16, 1261 (1977).Google Scholar
11. Levinson, L. M. and Philipp, H. R., J. Appl. Phys., 46, 1332 (1975).CrossRefGoogle Scholar
12. Philipp, H. R. and Levinson, L. M., J. Appl. Phys., 47, 3177 (1976).CrossRefGoogle Scholar
13. Levinson, L. M. and Philipp, H. R., J. Appl. Phys., 47, 1117 (1976).CrossRefGoogle Scholar
14. Zohta, Y., Sol. St. Electronics, 16, 1029 (1973).CrossRefGoogle Scholar
15. Shohata, N., Matsumura, T., and Ohno, T., Jap. J. Appl. Phys., 19, 1793 (1980).CrossRefGoogle Scholar
16. Nitayama, A., Sakaki, H., and Ikoma, T., Jap. J. Appl. Phys., 19, L743 (1980).CrossRefGoogle Scholar
17. Kroger, F. A., The Chemistry of Imperfect Crystals, (North Holland, Amsterdam, 1964) p. 691.Google Scholar
18. Einzinger, R., this proceedings.Google Scholar
19. Springett, B. E., Phys. Rev. Lett., 31, 1463 (1973).Google Scholar
20. Tomimuro, H. and Terasaki, Y., Jap. J. Appl. Phys., 18, 1653 (1979).CrossRefGoogle Scholar
21. Lou, L. F., Appl. Phys. Lett., 36, 570 (1980).CrossRefGoogle Scholar
22. Pike, G. E. and Seager, C. H., J. Appl. Phys., 50, 3414 (1979).CrossRefGoogle Scholar
23. Pike, G. E. and Seager, C. H., Adv. Ceramics, 1, 53 (1981).Google Scholar
24. Philipp, H. R. and Levinson, L. M., J. Appl. Phys., 47, 1112 (1976).CrossRefGoogle Scholar
25. Seager, C. H., Pike, G. E., and Ginley, D. S., Phys. Rev. Lett., 43, 532 (1979).Google Scholar
26. Robbins, D. J., Phys. Stat. Sol. (b), 97, 9 (1980).CrossRefGoogle Scholar