Different ‘‘single grain junctions’’ within a ZnO varistor

Abstract

The experimental part of this work describes a new method to determine the electrical characteristics of a single ZnO varistor grain‐to‐grain junction. The experimental results are described in statistical terms because each single barrier has been found to present its own electrical characteristics. There are ‘‘good’’ and ‘‘bad’’ barriers. On the basis of our experimental observations, we present an original approach to describing the current‐voltage characteristics of ZnO varistors from the characteristics of individual junctions (series or parallel models). Finally, this work demonstrates that a ZnO sample having a low thickness and a large nonlinear coefficient value requires only ‘‘good’’ junctions.