A study on the space charge distribution of ZnO varistor

This paper investigated the influence of varied additives/sintering condition on the performance of ZnO based on the space charge distribution measurements. Four kinds of ZnO based varistor samples have been tested. According to the experimental results, the space charge distributions are varied with different samples which were made from different formulas and varied sintering temperatures. The experimental results show that the space charge distribution of ZnO samples were stable and repeatable at a fixed applied DC voltage, therefore it might be used as a micro-parameter for evaluating of ZnO varistor. This is also helpful for understanding the mechanism of nonlinear V-I characteristics of ZnO and for developing higher performance varistors.