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。
Bilayered ferroelectric thin films, Ca0.4Sr0.6Bi4Ti4O15 grown on Bi3.25La0.75Ti3O12 , were prepared on (100) Si substrate by a sol-gel method. The thin films were annealed at 700 ℃ under air atmosphere. Phase structure, orientation and morphology of the bilayered ferroelectric thin films were characterized by X-ray diffraction (XRD) and Scanning Electron Microscope (SEM) respectively. At the same time, the P-E hysteresis loops of both films were measured. Compared with pure Ca0.4Sr0.6Bi4Ti4O15 thin film, Ca0.4Sr0.6Bi4Ti4O15 thin film grown on Bi3.25La0.75Ti3O12 seeding layer has larger a-axis orientation degree and larger grain size of about 80 nm. And there are less voids in bilayered ferroelectric thin films exhibiting a uniform and dense surface. Meanwhile, the bilayered ferroelectric thin film shows higher Pr =13.34 μC/cm 2 , and the corresponding coercive field is 68.32 kV/cm. The results suggest that Bi3.25La 0.75Ti3O12 film layer plays an important role on nucleation and crystallographic orientation of Ca0.4Sr0.6Bi4Ti4O15 thin film, and it is vital to the improvement of remanent polarization.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2013年第S1期22-25,共4页
Rare Metal Materials and Engineering
基金
国家自然科学基金资助(50872075,51272142)
关键词
溶胶-凝胶法
铁电薄膜
籽晶层
sol-gel
ferroelectric thin film
seeding layer
