利用同轴电子全息对纳米线中电荷分布的原位定量表征  

In-situ characterization of charge distribution in the nanowire by in-line holography

作　　者：刘诗凯 施特 陈琼阳 翟阿敏 田鹤[1] 丁泽军 李吉学[1] 张泽[1] LIU Shi-kai;SHI Te;CHEN Qiong-yang;ZHAI A-min;TIAN He;DING Ze-jun;LI Ji-xue;ZHANG Ze(Center of Electron Microscopy,State Key LaboratolT of Silicon Materials,and Department of Materials Science and Engineering,Hangzhou Zhejiang 310027,China)

机构地区：[1]浙江大学电子显微镜中心硅材料国家重点实验室材料科学与工程学院,浙江杭州310027

出　　处：《电子显微学报》2018年第5期414-420,共7页Journal of Chinese Electron Microscopy Society

基　　金：国家自然科学基金资助项目(No.11474249);国家重点基础研究计划(973计划)(No.2015CB654901)

摘　　要：纳米线及纳米管材料常被用于透射电镜中进行原位偏压下的电学测试,例如,对其场发射性能与电学击穿性质的测量,电场下电荷非均匀分布的信息可以使得我们对单根纳米线的性质做出更加定量的监控与判断。本文作者使用了同轴电子全息的方法,可以简单快捷地仅从单张离焦像中计算出沿纳米线的电荷分布。通过结合此方法与原位偏压技术,可以对在电场作用下碳化硅纳米线中的电荷分布进行成像,从无偏压时的均匀分布到受到电场调制后呈现出增大的梯度均可以被定量算出,且对电荷的灵敏度可优于1 e/nm。本方法可以应用于原位条件下进行快捷高效的动态电荷表征。Nanowires and nanotubes are usually used in the transmission electron microscope to perform the electrical measurement, such as the characterization of the field emission property and electrical breakdown under in-situ bias. The knowledge of the inhomogeneous charge distribution makes a more quantitative observation and control of the properties of individual nanowire. We demonstrate how in-line holography in transmission electron microscopy can be used to simply extract the charge distribution along the nanowire from single amplitude image.By taking advantage of the possibilities of in-situ biasing technology, the charge distribution and variations under electrical field can be imaged. The uniform distribution without biasing and the increasing charge gradient modulated by the field can be quantitatively measured. This method can realize a high sensitivity of 1 e/nm and allows for the fast and efficient acquisition of charges under external field.

关 键 词：透射电镜 同轴电子全息 原位电场 电荷分布 

分 类 号：TB383[一般工业技术—材料科学与工程] TB877