热致偏析构筑自适应垂直异质结  

Architecting adaptive vertical heterojunction by thermal segregation

作　　者：刘素贞 唐云龙 朱银莲[1,3] 曹毅 刘楠 刘嘉琦[1,2] 姜如建 王靖辉[1,2] 马秀良 LIU Su-zhen;TANG Yun-long;ZHU Yin-lian;CAO Yi;LIU Nan;LIU Jia-qi;JIANG Ru-jian;WANG Jing-hui;MA Xiu-liang(Shenyang National Laboratory for Materials Science,Institute of Metal Research,Chinese Academy of Sciences,Shenyang Liaoning 110016;School of Materials Science and Engineering,University of Science and Technology of China,Shenyang Liaoning 110016;Songshan Lake Materials Laboratory,Dongguan Guangdong 523808,China)

机构地区：[1]中国科学院金属研究所沈阳材料科学国家研究中心,辽宁沈阳110016 [2]中国科学技术大学材料科学与工程学院,辽宁沈阳110016 [3]松山湖材料实验室大湾区显微科学与技术研究中心,广东东莞523808

出　　处：《电子显微学报》2022年第5期535-541,共7页Journal of Chinese Electron Microscopy Society

基　　金：国家自然科学基金资助项目(Nos.51971223,51922100,52122101).

摘　　要：本文提出了一种基于传统钙钛矿铁电BiFeO_(3)薄膜制备具有优异电学性能复合纳米结构的方法,通过热致相分离在BiFeO_(3)基体中大规模构筑规则几何块状α⁃Fe_(2)O_(3)析出相。能谱分析显示α⁃Fe_(2)O_(3)相包覆于外缘富Bi层,暗示该氧化物形核于热扩散过程中Bi元素耗尽区。多尺度显微结构分析指出α⁃Fe_(2)O_(3)与基体保持特定的位向关系,进而与BiFeO_(3)构成垂直异质结。进一步利用多模式扫描探针显微镜表征了纵向异质界面处的电导行为。本研究呈现了一种利用热致偏析的动力学机制拓展传统钙钛矿氧化物功能性的方法,为研发设计低维多功能氧化物器件提供一种有效途径。Here we proposed a methodology of preparing nanocomposite thin films with excellent electrical properties based on traditional perovskite ferroelectrics.By thermally⁃driven chemical segregation,the hetero⁃system composed ofα⁃Fe_(2)O_(3) and BiFeO_(3) matrix has been constructed.EDS analysis revealed that the outer edge of the precipitatedα⁃Fe_(2)O_(3) was Bi⁃excessed,indicating that theαphase nucleated in the depletion region of Bi during thermal segregation process.Multi⁃scale microstructure analysis confirmed that theα⁃Fe_(2)O_(3) exhibits specific crystallographic orientation relationship with both the underlying substrate and the BiFeO_(3) matrix.Further electrical characterizations of the longitudinal hetero⁃interface have been performed by using scanning probe microscopy.This work suggests a way of extending the functionalities of traditional perovskite oxide by thermal segregation dynamic process,which should be expected to inspire the design of low⁃dimensional electrical devices.

关 键 词：BIFEO3薄膜 垂直异质结 透射电子显微镜 α⁃Fe2O3 

分 类 号：TB383[一般工业技术—材料科学与工程] O77[理学—晶体学] TG115.215.3[金属学及工艺—物理冶金]