不同电极对外延BiFeO_3薄膜铁电性能的影响  

Influence of Different Electrode on the Property of Epitaxial BiFeO_3 Thin Film

作　　者：马继奎[1] 赵庆勋[2] 彭增伟[2] 陈明敬[2] 史金超[1] 刘保亭[2] 

机构地区：[1]英利绿色能源控股有限公司,保定071051 [2]河北大学物理科学与技术学院,保定071002

出　　处：《人工晶体学报》2012年第6期1561-1565,共5页Journal of Synthetic Crystals

基　　金：国家自然科学基金(60876055;11074063);高等学校博士点基金(20091301110002);河北省自然科学基金(E2009000207;E2008000620;08B010)

摘　　要：采用磁控溅射的方法在SrRuO3/SrTiO3(001)衬底上外延生长BiFeO3薄膜,研究以不同金属或氧化物做顶电极时的铁电、铁磁性质和漏电流及其导电机制。X射线衍射图谱和Φ扫描图结果显示BiFeO3薄膜沿c轴外延生长,以Pt、Al做顶电极的薄膜剩余极化强度2Pr为68μC/cm2,生长Pt/SRO、FePt顶电极的薄膜剩余极化强度较小,2Pr为44μC/cm2,矫顽场2Ec约为370±20 kV/cm。薄膜的漏电流密度较小而且趋于饱和,在U=12 V时最大为1.94×10-3A/cm2,体传导普尔弗兰克导电为BiFeO3薄膜主要的导电机制。BFO薄膜展现出弱磁性,饱和磁化强度为9.3 emu/cm3,矫顽场为338 Oe。Epitaxial BiFeO3（BFO） thin film have been grown on SrRuO3/SrTiO3（001） substrates by radio frequency magnetron sputtering.Ferroelectric,ferromagnetic,leakage current and its mechanisms were investigates with different metal and conductive oxide top electrode.X-ray diffraction measurement and Φ scan spectra indicates the formation of an epitaxial single-phase.BFO film is well crystallized.The remnant polarization（2Pr） of BFO film by Pt and Al top electrode are 68 μC/cm2.They are 44 μC/cm2 by Pt /SRO and FePt top electrode at a coercive field（2Ec） of 370±20 kV/cm.The film has low leakage current density with largest of 1.94×10-3 A/cm2 at 12 V and Poole-Frenkle emission is the main conduction mechanism in BFO film.Moreover,BFO thin film exhibits a weak ferromagnetic behavior with a saturation magnetization of 9.3 emu/cm3 and a coercive field of 338 Oe.

关 键 词：BIFEO3 磁控溅射 铁电性 外延生长 

分 类 号：O484.1[理学—固体物理]