Effect of Ba_(0.5)Bi_(0.5)Fe_(0.9)Sn_(0.1)O_3 addition on electrical properties of BaCo_(0.02)~ⅡCo_(0.04)~ⅢBi_(0.94)O_3 thick-film thermistors  

Ba_(0.5)Bi_(0.5)Fe_(0.9)Sn_(0.1)O_3添加对BaCo_(0.02)~ⅡCo_(0.04)~ⅢBi_(0.94)O_3热敏厚膜电学性能的影响

作　　者：杨云[1] 袁昌来[1] 陈国华[1] 杨涛[1] 骆颖[2] 周昌荣[1] 

机构地区：[1]桂林电子科技大学材料科学与工程学院,桂林541004 [2]桂林电子科技大学信息通讯学院,桂林541004

出　　处：《Transactions of Nonferrous Metals Society of China》2015年第12期4008-4017,共10页中国有色金属学报（英文版）

基　　金：Projects(51102055;51462005)supported by the National Natural Science Foundation of China

摘　　要：Thick-film thermistor with negative temperature coefficient（NTC）, low room-temperature resistivity and modest thermistor constant was screen-printed on the alumina substrate by the combination of 30.94III0.04II0.02 B OBi Coa Co with Ba0.5Bi0.5Fe0.9Sn0.1O3. The electrical properties of the thick films were characterized by a digital multimeter, a Keithley 2400 and an impedance analyzer. The results show that with the Ba0.5Bi0.5Fe0.9Sn0.1O3 content increasing from 0.05 to 0.25, the values of room-temperature resistivity, thermistor constant and peak voltage of the thick films increases and are in the ranges of 1.47-26.5 ？·cm, 678-1345 K and 18.9-47.0 V, respectively. The corresponding current at the peak voltage of the thick films decreases and is in the range of 40-240 m A. The impedance spectroscopy measurement demonstrates that the as-prepared thick films show the abnormal electrical heterogeneous microstructure, consisting of high-resistive grains and less resistive grain boundary regions. It can be concluded that the addition of Ba0.5Bi0.5Fe0.9Sn0.1O3 into 30.94III0.04II0.02 Ba Co OBi Co improves the thermistor behavior and but also deteriorates the current characteristics.采用丝印法在铝基板上制备具有低室温电阻率、适中热敏常数的负温度系数BaCo0.02ⅡCo0.04ⅢBi0.94O3/Ba0.5Bi0.5Fe0.9Sn0.1O3复合热敏厚膜。采用数字多用表、吉时利2400和阻抗分析仪对热敏厚膜的电学性能进行表征。结果表明：随着Ba0.5Bi0.5Fe0.9Sn0.1O3含量从0.05增加至0.25,厚膜的室温电阻率、热敏常数和峰值电压均有所增加且分别处于1.47-26.5Ω·cm、678-1345 K和18.9-47.0V范围内,厚膜峰值电压对应的电流也有所降低且处于40-240 mA范围。阻抗谱测试表明,这些热敏厚膜表现出非正常的异质电学微结构行为,由高阻态的晶粒和较低电阻态的晶界区域构成。由此可知,在BaCo0.02ⅡCo0.04ⅢBi0.94O3中添加Ba0.5Bi0.5Fe0.9Sn0.1O3改善了热敏行为但也恶化了电流特征.

关 键 词：NTC thick films BaCo0.02ⅡCo0.04ⅢBi0.94O3 Ba0.5Bi0.5Fe0.9Sn0.1O3 electrical property 

分 类 号：TG174.4[金属学及工艺—金属表面处理]