(Oscillation Characteristics in the Intergranular Layer of ZnO Varistor Fabricated 3-Composition Seed Grain Method)

3-성분 종입자법으로 제조한 ZnO 바리스터의 입계모델에서 발진특성

In this paper, the samples are made by the new three-composition seed grain method, in order to obtain the low voltage varistor distributed randomly large seed grain in its bulk. The oscillation phenomena of carriers appeared from current-voltage characteristics under knee voltage is shown by the transient flow of non trapped carriers group in the trap level of intergranular layer, surface state and/or depletion layer. Current oscillation phenomena is hardly shown in the high electric field. The injected carriers from both electrodes are directly flowed from the conduction band of forward biased grain through the intergranular layer into the reverse biased grain, because the trap level in the electric field above the knee voltage is mostly filled.