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The Effect of Microstructure Nonuniformity on the Electrical Characteristics of ZnO Varistors with $Al_2$O$_3$ doping  

Han, Se-Won (KERI (Korea Electrotechnology Research Institute))
Cho, Han-Goo (KERI (Korea Electrotechnology Research Institute))
Publication Information
KIEE International Transactions on Electrophysics and Applications / v.3C, no.4, 2003 , pp. 140-145 More about this Journal
Abstract
The influence of microstructure nonuniformity on the electrical characteristics of ZnO varistors was analyzed with the added amount of $Al_2$O$_3$ dopants. $Al_2$O$_3$ doping can effectively inhibit grain growth. When $Al_2$O$_3$ content is in the range between 0-0.1 %, the average grain size and the standard deviation decrease quickly and the grain growth is strongly inhibited. Therefore, it is possible to increase the microstructure uniformity by accurate addition of $Al_2$O$_3$ to the ZnO varistor. The breakdown voltage increases with the decrease of standard deviation. The greater the uniformity of the Zno varistor means the higher the global breakdown voltage. The $Al_2$O$_3$ dopants having about 0-0.023 wt% content can effectively improve the voltage ratio, and the voltage ratio reaches a minimum value of 2.32 at an $Al_2$O$_3$ content of 0.005 wt%.
Keywords
ZnO Varistor; A1$_2$O$_3$ Doping; Microstructure Nonuniformity; Electrical Properties; Standard Deviation;
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Times Cited By KSCI : 1  (Citation Analysis)
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1 J.L. He, S. C. Chen, S. W. Han, H. G. Cho, 'Statistic analysis on nonuniformity of electrical parameters of ZnO varistors', JEEIS, Vol. 3 [5], pp. 631-637, 1998.
2 M. Matsuoka, 'Nonohmic properties of Zinc oxide ceramics', Jpn. J. Appl. Phys. Vol. 10 [6], pp. 36-46, 1971.
3 H. D. Hwang, S. W. Han, H. B. Kann, 'The embodiment of real ZnO varistor and the analysis of electrical properties with Voronoi network', The Transactions of The Korean Institute of Electrical Engineers, Vol.47 [5], pp. 607-613, 1998.
4 L. M. Levinson and H. R. Philipp, 'Zinc oxide varistors, a review', Am. Ceram. Soc. Bull., Vol. 65 [4], pp. 639-47, 1986.
5 T. Senda and R. C. Bradt, 'Grain growth in Zinc oxide during the sintering of Zinc oxide-antimony oxide ceramics', J. Am. Ceram. Soc., Vol. 74 [6], pp. 1296-1302, 1991.
6 W. G. Carlson and T. K. Gupta, 'Improved varistor nonlinearity via donor impurity doping', J. Appl. Phys. Vol. 53 [8], pp. 5746-53, 1982.
7 K. Eda, 'Zinc oxide varistors,' IEEE Electrical Insulation Magazine, Vol.5 [6], pp. 28-41, 1989.
8 M. Trontelj and V. Krasevec, 'Effects of antimony oxide in the sintering of ZnO varistors', pp. 108-116, in Ceramics Transactions, Vol. 3: Advances in varistor technology, edited by L. M. Levinson, the American Ceramic Society, Inc., Westerville, Ohio, 1988
9 H. Wang, W. Li and J. F. Cordaro, 'Single junction in ZnO varistors studied by current-voltage characteristics and deep level transient spectroscopy', Jpn. J. Appl. Phys., Vol.34 [4A], pp. 1765-71, 1995.
10 S. W. Han, H. B. Kang, 'Effect of $Al_{2}O_{3}$ as dopants on the complex impedance and J-E behavior of ZnO-$Bi_{2}O_{3}$ varistor', The Transactions of The Korean Institute of Electrical Engineers, Vol. 46 [10], pp. 1502-1508, 1997.
11 T. Takemura, M. Kobayashi, Y. Takada and K. Sato, 'Effects of aluminum as dopant on the characteristics of ZnO varistors', Advances in Ceram. Vol. 29 [2], pp. 101-06, 1992.