Bi_(3.25)La_(0.75)Ti_3O_(12)籽晶层对Ca_(0.4)Sr_(0.6)Bi_4Ti_4O_(15)铁电薄膜的影响  

Effect of Bi_(3.25)La_(0.75)Ti_3O_(12) Seeding Layer on Ca_(0.4)Sr_(0.6)Bi_4Ti_4O_(15) Thin Film

作　　者：王营营[1] 范素华[2] 张丰庆[1] 尹军[1] 

机构地区：[1]山东建筑大学,山东济南250101 [2]山东女子学院,山东济南250300

出　　处：《稀有金属材料与工程》2013年第S1期10-12,共3页Rare Metal Materials and Engineering

基　　金：国家自然科学基金资助(50872075;51272142)

摘　　要：用溶胶-凝胶法在Si(100)基片上沉积Ca0.4Sr0.6Bi4Ti4O15/Bi3.25La0.75Ti3O12双层膜,薄膜置于空气气氛在退火炉中700℃退火处理。用X射线衍射(XRD)和扫描电镜(SEM)分别对薄膜的相结构、取向度和微观形貌进行表征,并测试了样品的电滞回线。结果表明:与纯的Ca0.4Sr0.6Bi4Ti4O15铁电薄膜相比,双层膜具有更高的a轴取向度,表面均匀致密无孔隙,多为球形晶粒,且晶粒尺寸约为80nm,并且具有较高的剩余极化强度Pr=13.34μC/cm2,对应的矫顽场强为68.32kV/cm;Bi3.25La0.75Ti3O12的引入对Ca0.4Sr0.6Bi4Ti4O15铁电薄膜的形核生长和晶体学取向具有一定的促进作用,有利于样品的铁电性能。CSBT (Ca0.6Sr0.4Bi4Ti4O15 ) thin films were prepared on LNO (LaNiO3 ) substrates by Sol-gel method. The influence of spin-coating speed, thermal decomposition temperature, and annealing temperature on CSBT/LNO film orientation and performance were discussed. The best preparation conditions of (200)-oriented CSBT/LNO film were: spin-coating speed of 4000 r/min, thermal-decomposition temperature of 400 ℃, and annealing temperature of 725 ℃. In this case, the patterns of X-ray diffraction (XRD) exhibit no secondary phase (such as pyrochlore phase) indicating a pure perovskite phase in the sample with I (200) /I (119) =1.26. The film shows well hysteresis loop with remnant polarization (2Pr) and coercive field (2Ec) as 36.7 μC/cm2 and 156 kV/cm, respectively. The dielectric constant of CSBT/LNO film is 215 showing its good frequency stability.

关 键 词：热处理温度 CSBT/LNO薄膜 铁电性能 

分 类 号：TB383.2[一般工业技术—材料科学与工程]