外延BiFeO_3薄膜的TEM显微结构表征  

Quantitative analysis of microstructure in epitaxial BiFeO_3 film by TEM

作　　者：张腾[1] 于荣[1] 朱静[1] 詹倩[2] 朱英豪[3] 

机构地区：[1]清华大学材料系北京电子显微镜中心,北京100084 [2]北京科技大学材料学院,北京100083 [3]台湾交通大学,台湾新竹30010

出　　处：《电子显微学报》2012年第4期281-285,共5页Journal of Chinese Electron Microscopy Society

基　　金：国家自然科学基金资助项目(No.51071092);教育部留学回国人员科研启动基金资助项目(No.50971015);教育部全国百篇优秀博士论文作者专项;科技部创新方法项目(No.2010IM031300)

摘　　要：外延BiFeO3薄膜中丰富的结构与特殊的性能一直是近年来研究的热点。显微结构的研究不仅可以帮助人们进一步认识BiFeO3的结构信息,还可以帮助人们深入了解BiFeO3结构与性能间的关系,开拓新的应用领域。本文利用球差校正高分辨透射电子显微镜对外延在LaAlO3过渡层/Si基底上的BiFeO3薄膜进行研究。通过原子尺度的定量分析,在应力状态复杂区域观察到类菱方相、应力释放后恢复的菱方相以及拉应力状态下c/a值小于1的类菱方相,并在该区域观察到109°铁电畴,且畴间存在4.4°的畸变夹角。还观察到比较大的c/a比。Recently,epitaxial BiFeO3 films have been intensively studied due to their exotic phase structures and properties.The investigation about the microstructure of BiFeO3 might shed light on the relationship between structures and properties.In this paper,the Cs-corrected TEM is used to study the microstructure of epitaxial BiFeO3 films on the LaAlO3 buffer/Si substrate.By quantitative analysis of atomic positions of Bi and Fe,the 109°ferroelectric domain wall with 4.4°distortion angle composed by was identified.Relatively large c/a ratio in regions with complicate strain condition was also observed.

关 键 词：多铁性 高分辨电子显微术 铁电畴 菱方相 

分 类 号：TB34[一般工业技术—材料科学与工程] O76[理学—晶体学]