A Review of the Zinc Oxide Varistor.

Abstract

The nonlinear electrical characteristic of zinc oxide varistors is explored in terms of the ceramic sintering process, i. e., sintering temperature, oxide admixture, grain growth, intergranular layer thickness, etc. The property of non-ohmic conduction is traced to the presence of a segregated second-phase accumulation layer, which surrounds the ZnO grains, and acts as an insulating potential barrier. The transition region from ohmic to non-ohmic conduction (prebreakdown region) is explained by the Poole-Frenkel effect in which, for low applied fields, conduction takes place by thermal activation over the field-lowered barrier. In the highly conductive (breakdown) region, conduction corresponds with Fowler-Nordheim field-assisted tunneling. Although Space-Charge-Limited-Conduction (SCLC) theory is considered, it does not appear to be applicable. (Author)

Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1975
Accession Number
ADA019365

Entities

People

  • Morris Campi

Organizations

  • Harry Diamond Laboratories

Tags

Communities of Interest

  • Advanced Electronics

DTIC Thesaurus Topics

  • Grain Growth
  • Growth (General)
  • Quantum Tunneling
  • Sintering
  • Space Charge
  • Thickness
  • Transitions
  • Tunneling
  • Varistors

Fields of Study

  • Materials science

Readers

  • Plasma Physics.
  • Powder metallurgy of Titanium alloys.
  • Semiconductor Device Technology

Technology Areas

  • Microelectronics
  • Microelectronics - Graphene
  • Space