La掺杂BiFeO3薄膜铁电及光学性能研究  

Study on Ferroelectric and Optical Properties of La-doped BiFeO3 Films

作　　者：杨松 郭凯鑫 张敏 邓朝勇 王旭 YANG Song;GUO Kai-xin;ZHANG Min;DENG Chao-yong;WANG Xu(College of Big Data and Information Engineering,Guizhou University,Guiyang 550025,China)

机构地区：[1]贵州大学大数据与信息工程学院

出　　处：《人工晶体学报》2019年第8期1445-1450,1456,共7页Journal of Synthetic Crystals

基　　金：国家自然科学基金(61404033);贵州大学国家级重点(重大)培育项目资助项目(201813);贵州省公共大数据重点实验室开放课题(2017BDKFJJ)

摘　　要：利用溶胶-凝胶法分别在Pt/TiO2/SiO2/Si和ITO/玻璃衬底上制备纯相的铁酸铋(BiFeO3)和La掺杂的铁酸铋(Bi1-xLaxFeO3,x=0.05,0.1)薄膜。XRD测试表明BLFO薄膜为纯钙钛矿相,都呈(111)方向的菱形结构,La掺杂可以提高BFO薄膜的结构稳定性。镧掺杂铁酸铋具有更大的剩余极化值和较小的漏电流。此外,随着La成分的增加,薄膜的基本吸收边呈现红移,并通过Tauc公式计算拟合观察到BLFO的光学带隙逐渐减小。结果发现随着La掺杂量(0,5mol%,10mol%)逐渐增大,薄膜的剩余极化值越大,其禁带宽度(Eg)越小。Bi 1- x La x FeO 3( x =0,0.05,1) films were deposited on ITO/glass and Pt/Ti/SiO 2/Si substrates by Sol-gel technique. XRD measurements show that BLFO films are of a (111) oriented rhombic perovskite structure and the introduction of La can further improve the structural stability of the BFO films. Lanthanum doped bismuth ferrite presents a larger residual polarization value but a smaller leakage current. Moreover, with the increasing of the content of La 3+, the fundamental absorption edges of BLFO films exhibit red shift and the optical bandgaps of BLFO decreases gradually by calculating and fitting with Tauc formula. The results indicate that as the La doping increases(0, 5mol%, 10mol%) larger the residual polarization, the smaller the band gap E g .

关 键 词：漏电流 容限因子 铁电性 光学带隙 

分 类 号：O484.4[理学—固体物理]