TiO_2掺杂导致的SnO_2压敏陶瓷晶粒尺寸效应  

Grain Size Effects of (Nb,Co)-doped SnO_2 Varistors Ceramics Induced by TiO_2-dopant

作　　者：明保全[1] 王矜奉[1] 陈洪存[1] 苏文斌[1] 臧国忠[1] 高建鲁 

机构地区：[1]山东大学物理与微电子学院,山东济南250100 [2]济南安太电子研究所,山东济南250010

出　　处：《电子元件与材料》2004年第6期20-22,27,共4页Electronic Components And Materials

基　　金：山东省自然科学基金资助项目(Z2003F04)

摘　　要：研究了TiO2掺杂对SnO2-Co2O3-Nb2O5系压敏陶瓷材料电学性能的影响。掺入x(TiO2)为1.00%的陶瓷样品具有最高的密度(r = 6.82 g/cm3),最高的视在势垒电场(EB= 476 V/mm),最高的非线性系数(a = 11.0),最小的相对介电常数。未掺杂的样品阻抗最大。随TiO2掺杂量的增加晶粒逐渐变小,晶粒尺寸的减小归因于未固溶于SnO2晶格而偏析在晶界上的TiO2阻碍相邻SnO2晶粒融合。为了解释SnO2-Co2O3-Nb2O5-TiO2系电学非线性性质的根源,对前人的晶界缺陷势垒模型进行了修正。Investigated were the effects of TiO2 on the electrical properties of (Nb , Co)-doped SnO2 varistors ceramics. Obtained ceramic samples (SnO2-Co2O3-Nb2O5 system) have the highest density (r = 6.82 g/cm3), the highest varistor field (EB = 476 V/mm), the highest nonlinear coefficient (a=11.0) and the lowest relative dielectric constant when 1 mol% TiO2 was doped. The SnO2 grain size decreases with increase of TiO2 amount. In order to explain the origin of the voltage nonlinearity for SnO2-Co2O3-Nb2O5-TiO2 varistor ceramics, a modified grain-boundary defect barrier model was proposed.

关 键 词：压敏材料 二氧化锡 电学性能 晶粒尺寸 缺陷势垒模型 TiO2掺杂 SNO2 

分 类 号：TN304.43[电子电信—物理电子学]