Structural and Electrical Characters of Ba_(0.6)Sr_(0.4)TiO_3/La_(0.5)Sr_(0.5)CoO_3 Thin Films by Plus Laser Deposition

作     者：Wen-Feng Qin Jun Zhu Jie Xiong Jin-Long Tang Xiao Feng 

作者机构：State Key Laboratory of Electronic Thin Film and Integrated Devices University of Electronic Science and Technology of China （UESTC） Chcngdu 610054 China 

出 版 物：《Journal of Electronic Science and Technology of China》 (中国电子科技（英文版）)

年 卷 期：2007年第5卷第4期

页      面：303-307页

学科分类：08[工学] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：This work was supported by the youth science and technology fund of University of Electronic Science and Technology of China No.L08010301JX0617 

主　　题：BST electrode LSCO thin film. 

摘      要：Epitaxial Ba0.6Sr0.4TiO3 （BST） thin films were deposited on LaAlO3 （LAO） substrates with the conductive metallic oxide La0.5 Sr0.5CoO3 （LSCO） film as a bottom electrode by pulsed laser deposition （PLD）. X-ray diffraction 0-20 andФ scan showed that the epitaxial relationship of BST/LSCO /LAO was [001] BST// [001] LSCO//[001] LAO. The atomic force microscope （AFM） revealed a smooth and crack-free surface of BST films on LSCO-coated LAO substrate with the average grain size of 120 nm and the RMS of 1.564 nm for BST films. Pt/BST/LSCO capacitor was fabricated to perform Capacitance-Voltage measurement indicating good insulating characteristics. For epitaxial BST film, the dielectric constant and dielectric loss were determined as 471 and 0.03, respectively. The tunabilty was 79.59% and the leakage current was 2.63×10^-7 A/cm^2 under an applied filed of 200 kV/cm. Furthermore, it was found that epitaxial BST （60/40） fdms demonstrate well-behaved ferroelectric properties with the remnate polarization of 6.085μC/cm^2 and the coercive field of 72 kV/cm. The different electric properties from bulk BST （60/40） materials with intrinsic paraelectric characteristic are attributed to the interface effects.