Nonlinear Electrical Characteristics of Antimony and Copper Doped Tin Oxide Based Varistor Ceramics

摘要

@@ The novel CuO-doped dense tin oxide varistor ceramics are investigated. The densification of tin oxide varistor ceramics could be greatly improved by doping copper oxide additives. The introduction of antimony additives into a SnO2.CuO ceramic system would make it possess excellent nonlinearity. The sample doped with 0.05mol% Sb2 O3 possesses the highest nonlinearity coefficient (α = 17.9) and the lowest leakage current density ( JL = 52 μA cm-2 ) among all the samples. A modified defect barrier model is introduced to explain the formation of the grain boundary barrier. The nonlinear behaviour of (Cu, Sb)-doped SnO2 varistor system could be explained by the barrier model.