標題: THE EFFECTS OF ND2O3 ADDITIVES AND AL2O3-SIO2-TIO2 SINTERING AIDS ON THE ELECTRICAL-RESISTIVITY OF (BA,SR)TIO3 PTCR CERAMICS
作者: LAI, CH
WENG, CT
TSENG, TY
電子工程學系及電子研究所
Department of Electronics Engineering and Institute of Electronics
關鍵字: POSITIVE TEMPERATURE COEFFICIENT OF RESISTANCE;ACCEPTOR STATE DENSITY;GRAIN BOUNDARIES;PERMITTIVITY;BARRIERS
公開日期: 1-四月-1995
摘要: The influences of Nd donors and Al2O3-SiO2-TiO2 (AST) sintering aids on the electrical properties of (Ba,Sr)TiO3 materials have been investigated. The room-temperature resistivity and the temperature coefficient of the anomalous resistivity rise were used to characterize the performance of the samples. From derivations based on the Heywang-Jonker barrier model, both characterizing parameters are expected to increase as a result of higher acceptor-state density at the grain boundary. The surface acceptor density, whose value was extracted from the slope in the Arrhenius plot of resistivity versus 1/(T epsilon(m)), where epsilon(m) is the measured permittivity and T the absolute temperature, was found to decrease with the Nd content and increase with the AST dopant. A satisfactory interpretation of the observed variations in resistivity-temperature curves caused by additions of various dopants was thus obtained in the light of the resultant acceptor state density.
URI: http://hdl.handle.net/11536/1990
ISSN: 0254-0584
期刊: MATERIALS CHEMISTRY AND PHYSICS
Volume: 40
Issue: 3
起始頁: 168
結束頁: 172
顯示於類別:期刊論文


文件中的檔案:

  1. A1995RA33600003.pdf