低温烧结多层片式ZnO压敏电阻内电极 Ag含量对电性能的影响

研究了低温烧成多层片式ZnO压敏电阻的内电极中Ag扩散进入ZnO晶格对电性能的影响．研究发现内电极中Ag含量严重影响低温烧结多层片式压敏电阻的电性能．当内电极含Ag量为70％时，具有最好的电性能；而内电极为纯Ag时，电性能最差，压敏电压和限制电压过分地升高，漏电流增大，非线性系数减小．反映晶界势垒电容的电容量随内电极中Ag含量的升高而减小．伏安特性和复数阻抗分析表明，随着内电极中Ag含量的升高，Ag扩散进入ZnO晶格加剧，降低了施主浓度Nd，导致ZnO晶粒电阻增大，以及晶界势垒高度和耗尽层宽度增加，使得多层片式ZnO压敏电阻的电性能变差．

Effect of Ag diffusion on electrical properties of multilayer varistor

Effect of Ag diffusion in inner electrode on electric properties of multilayer chip ZnO varistor(MLCV) was studied.The results showed that Ag content in inner electrode plays a very important role in the electric properties of MLCV.Among the studied 3 compositions of the electrode pastes,the properties of MLCV whose inner electrode containing 70% Ag was the best;and those of MLCV having pure Ag inner electrode was the worst.The analyses of V-I characteristics curves and complex impedances indicated that,during the co-firing process of the ceramic and inner electrode,with the increase of Ag content in inner electrode,the velocity of Ag diffusing in the ZnO lattice speeded,and the grain resistance increased excessively,and the electric properties of MLCV deteriorated.