还原再氧化工艺下BaTiO_3基PTCR元件的密度与其电性能  

Relationship between Density and Electrical Characteristics of BaTiO_3 Based Thermistor Sintered in Reducing Atmosphere and Reoxidized in Air

作　　者：胡云香[1] 赵程程[1] 傅邱云[1] 龚树萍[1] 周东祥[1] 

机构地区：[1]华中科技大学电子科学与技术系,湖北武汉430074

出　　处：《仪表技术与传感器》2011年第10期4-6,40,共4页Instrument Technique and Sensor

基　　金：国家"863"计划资助项目(SQ2008AA03Z4471960)

摘　　要：通过固相法制备出正温度系数热敏电阻(PTCR)传感器,并且通过烧结过程控制瓷体密度。还原气氛中烧结的瓷片的电阻率随着密度的升高呈现逐渐降低的趋势,而再氧化后的瓷片的PTC效应随着密度的升高也呈现逐渐降低的趋势。含有内电极的电阻元件,相对于不含内电极的瓷片,电阻率有所升高,PTC效应有所降低,且密度越低,含有内电极的元件相对于不含内电极的瓷片的电性能变化更明显。相对密度在75%～83%之间的瓷片,在空气中650℃再氧化1h后,其电阻率为60～120Ω.cm,PTC效应为2.0～2.3个数量级,同一条件下的含有单对Ni电极的元件,其电阻率在200Ω.cm以下,PTC效应可达1.5个数量级。Donor-doped positive temperature coefficient thermistors were prepared through solid state method and the density of ceramics were controlled through the sintering process. Results show that room temperature resistivity of samples sintered in reducing atmosphere decreases along with the density increases. The positive temperature coefficient of resistivity characteristics of ceramics after re-oxidized in air goes down with the rising of density. One-layer elements with one pair of nickel internal electrodes, compared to single plates, the room resistivity increases while the PTC effect decreases. The lower the density is, the larger the gap of electrical characteristics becomes. The room temperature resistivity of ceramics with the relative density of 75% to 83% is between 60 and 120 Ω·cm with the PTC jump of 2. 0 to 2. 3 magnitudes after re-oxidized at 650℃ in air for 1 hour while the Nicontained ones dealt under the same condition have the resistivity below 200 Ω·cm and PTC jump of over 1.5 magnitudes.

关 键 词：密度 室温电阻率 PTC效应 

分 类 号：TN373[电子电信—物理电子学]