Hostname: page-component-7c8c6479df-xxrs7 Total loading time: 0 Render date: 2024-03-29T06:03:46.168Z Has data issue: false hasContentIssue false

Improved stability of the ZnO varistor via donor and acceptor doping at the grain boundary

Published online by Cambridge University Press:  31 January 2011

T. K. Gupta
Affiliation:
Ceramics Division, Alcoa Laboratories, Alcoa Center, Pennsylvania 10569
A. C. Miller
Affiliation:
Ceramics Division, Alcoa Laboratories, Alcoa Center, Pennsylvania 10569
Get access

Abstract

The ZnO varistor degradation has been attributed to the field-assisted, temperature-activated diffusion of interstitial zinc in the depletion layer. To improve stability, one approach is to reduce the formation of interstitials, and then further, to prevent their migration through empty interstitial sites. Based on this concept, an amphoteric dopant, such as Na or K, has been incorporated in the ZnO varistor grain boundary wherein a dopant is substituted both in the lattice and in the interstitial sites. A grain boundary defect model has been developed for this dual mode of substitution, with the dopant acting as an acceptor at the lattice site and as a donor at the interstitial site. Under these conditions, and given a desired neutrality range, the concentration of zinc interstitial is indeed shown to be reduced and stability greatly improved. The experimental data presented here validate the grain boundary defect model presented in this and in an earlier paper [J. Mater. Sci. 20, 3487 (1985)].

Type
Articles
Copyright
Copyright © Materials Research Society 1988

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

REFERENCES

1Gupta, T. K. and Carlson, W. G.J. Mater. Sci. 20, 3487 (1985).Google Scholar
2Carlson, W. G.Gupta, T. K. and Sweetana, A.IEEE Trans. Power Delivery PWRD-1 (2), 67 (1986).Google Scholar
3Sakshaug, E. C.Kresge, J. S. and Miske, S. A.IEEE Trans. Power Appar. Syst. PAS-96 (2), 647 (1977).Google Scholar
4Eda, K.Iga, A. and Matsuoka, M.Jpn. J. Appl. Phys. 18, 997 (1979).CrossRefGoogle Scholar
5Eda, K.Iga, A. and Matsuoka, M.J. Appl. Phys. 51, 2678 (1980).Google Scholar
6Shirley, C. G. and Paulson, W. M.J. Appl. Phys. 50, 5782 (1979).Google Scholar
7Sato, K.Takada, Y.Maekawa, H.Ototake, M. and Tominaga, S.Jpn. J. Appl. Phys. 19, 909 (1980).Google Scholar
8Tominaga, S.Shibuya, Y.Fujiwara, Y.Imataki, M. and Nitta, T.IEEE Trans. Power Appar. Syst. PAS-99 (4), 1548 (1980).Google Scholar
9Moldenhauer, W.Bather, K. H.Bruckner, W.Hizn, D. and Buhling, D.Phys. Status Solidi A 67, 533 (1981).Google Scholar
10Gupta, T. K.J. Mater. Res. 2, 231 (1987).Google Scholar
11Gupta, T. K.Carlson, W. G. and Hower, P. L.J. Appl. Phys. 52, 4104 (1981).Google Scholar
12Gupta, T. K. and Carson, W. G. in Advances in Ceramics, edited by Yan, M. F. and Heuer, A. H. (American Ceramic Society, Columbus, OH, 1983), Vol. 7, pp. 3040.Google Scholar
13Gupta, T. K.Carson, W. G. and Hall, B. O. in Grain Boundaries in Semiconductors, edited by Pike, G. E.Seager, C. H. and Leamy, H. J. (Elsevier, New York, 1982), pp. 393397.Google Scholar
14Gupta, T. K. and Carlson, W. G.J. Appl. Phys. 53, 7401 (1982).Google Scholar
15Gupta, T. K.Carlson, W. G. and A.Sweetana, S. U.S. Patent No. 4, 460, 497, July 17, 1984.Google Scholar
16Miyoshi, T.Maeda, K.Takahashi, K. andYamazaki, T. in Advances in Ceramics, edited by Levinson, L. M. (American Ceramic Society, Columbus, OH, 1981), Vol. 1, pp. 309315.Google Scholar
17Takemura, T.Kobayashi, M.Takada, Y. and Sato, K. in Advances in Cer imics, edited by Yan, M. and Heuer, A. H. (American Ceramic Socify, Columbus, OH, 1983), Vol. 7, pp. 5059.Google Scholar
18Vakemura, T., Kobayashi, M.Takada, Y. and Sato, K.J. Am. Ceram. Soc. 69, 430 (1986).Google Scholar
19Carlson, W. G. and Gupta, T. K.J. Appl. Phys. 53, 5746 (1982).CrossRefGoogle Scholar
20Matsuoka, M.Jpn. J. Appl. Phys. 10, 736 (1971).Google Scholar
21Levinson, L. M. and Phillip, H. R.J. Appl. Phys. 46, 1332 (1975).Google Scholar
22Hower, P. L. and Gupta, T. K.J. Appl. Phys. 50, 4847 (1979).CrossRefGoogle Scholar
23Pike, G. E. in Grain Boundaries In Semiconductors, edited by Leamy, H. J.Pike, G. E. and Seager, C. H. (Elsevier, New York, 1982), pp. 369379.Google Scholar
24Levin, J. D.CRC Crit. Rev. Solid State Sci. 5, 597 (1975).Google Scholar
25Rice, R. W. in Materials Science Research, edited by Krigel, W. W. and Palmour, H. III (Plenum, New York, 1966), Vol. 3, p. 387.Google Scholar
26Clarke, D. R.J. Appl. Phys. 49, 2407 (1978).CrossRefGoogle Scholar
27Yan, M. F.Cannon, R. M.Bowen, K. E. and Coble, R. L.J. Am. Ceram. Soc. 60, 120 (1977).Google Scholar
28Kroger, F. A.The Chemistry of Imperfect Crystals (Wiley, New York, 1964), p. 691.Google Scholar
29Selim, F. A.Gupta, T. K.Hower, P. L. and Carlson, W. G.J. Appl. Phys. 51, 765 (1980).Google Scholar
30Sukkar, M. H. and Tuller, H. L. in Advances in Ceramics, edited by Yan, M. F. and Heuer, A. H. (American Ceramic Society, Columbus, OH, 1983), Vol. 7, pp. 7190.Google Scholar
31Kawaguchi, T.Yoshida, H. and Kawai, H.Denshi Shashin Electro-photography 7, 24 (1966).Google Scholar