(Sr,Co,Nb)掺杂SnO_2压敏电阻的电学非线性  

Nonlinear electrical properties of (Sr, Co, Nb)-doped SnO_2 varistors

作　　者：亓鹏[1] 王矜奉[1] 陈洪存[1] 苏文斌[1] 王文新[1] 臧国忠[1] 王春明[1] 

机构地区：[1]山东大学物理与微电子学院晶体材料国家重点实验室,济南250100

出　　处：《物理学报》2003年第7期1752-1755,共4页Acta Physica Sinica

基　　金：国家自然科学基金 (批准号 :5 0 0 72 0 13 )资助的课题~~

摘　　要：研究了Sr对新型 (Co ,Nb)掺杂SnO2 压敏材料微观结构和电学性质的影响 .当SrCO3的含量从零增加到1 5 0mol%时 ,(Co ,Nb)掺杂SnO2 压敏电阻的击穿电压从 2 4 0V mm猛增到 14 82V mm .样品的微观结构分析发现 ,当SrCO3的含量从零增加到 1 5 0mol%时 ,SnO2 的晶粒尺寸迅速减小 .晶界势垒高度测量揭示 ,SnO2 晶粒尺寸的迅速减小是击穿电压急剧增高的主要原因 .对Sr含量增加引起SnO2 晶粒减小的根源进行了解释 .掺杂 1 5 0mol%SrCO3的SnO2 压敏电阻非线性系数为 2 1 4 ,击穿电压高达 14 82VThe effect of Sr on the microstructure and nonlinear electrical properties of the (Co, Nb)-doped SnO2 varistors was investigated. The breakdown voltage of the SnO2-based varistors increased significantly from 240 to 1482V/mm with increasing SrCO3 concentration from 0 to 1.50 mol%. Measurement of the barrier height at grain boundaries reveal that the significant decrease of the SnO2 grain size with increasing SrCO3 concentration from 0 to 1.50 mol%, is the reason of the enhancement of the breakdown voltage. The origin for the reduction of SnO2 grain size with increasing SrCO3 concentration was explained. The 1.50 mol% SrCO3 -doped SnO2 varistor with ultrahigh breakdown voltage (1482V/mm) and larger nonlinear coefficient alpha(21.4) is, a candidate used in the ultrahigh voltage protection system.

关 键 词：SnO2 压敏电阻 电学非线性 二氧化锡 微观结构 势垒 SrCO3 碳酸锶 压敏电阻器 (Sr Co Nb)掺杂 

分 类 号：O482.41[理学—固体物理]