Effect of variations in grain size and grain boundary barrier heights on the current-voltage characteristics of ZnO varistors
- Univ. of California, Santa Barbara, CA (United States)
Throughout the microstructure at every varistor, there exist variations of the grain size and the electrical properties of the individual grain boundaries. To calculate the effect of such microstructural variations on the overall electrical transport properties, the authors describe a multibond percolation approach utilizing effective medium theory. The model presented takes into account these variations as well as the electrical conductivity of the ZnO grains themselves. To illustrate the predictions of the model, both the effect of continuous distributions in the grain boundary potential and the grain size are considered, as well as a bi-lognormal distribution in grain size to represent the effect of a population of anomalously large grains in a smaller grain size varistor.
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- FG03-91ER45447
- OSTI ID:
- 422725
- Journal Information:
- Journal of the American Ceramic Society, Journal Name: Journal of the American Ceramic Society Journal Issue: 12 Vol. 79; ISSN 0002-7820; ISSN JACTAW
- Country of Publication:
- United States
- Language:
- English
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