Han W, Zheng M, Banerjee A, Luo Y Z, Shen L, Khursheed A
Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore, 117583, Singapore.
Physics Department, Bidhan Chandra College, Kazi Nazrul University, Asansol, West Bengal, 713303, India.
Sci Rep. 2020 Dec 17;10(1):22144. doi: 10.1038/s41598-020-78973-0.
This paper demonstrates how secondary electron energy spectroscopy (SEES) performed inside a scanning electron microscope (SEM) can be used to map sample atomic number and acquire bulk valence band density of states (DOS) information at low primary beam voltages. The technique uses an electron energy analyser attachment to detect small changes in the shape of the scattered secondary electron (SE) spectrum and extract out fine structure features from it. Close agreement between experimental and theoretical bulk valance band DOS distributions was obtained for six different test samples, where the normalised root mean square deviation ranged from 2.7 to 6.7%. High accuracy levels of this kind do not appear to have been reported before. The results presented in this paper point towards SEES becoming a quantitative material analysis companion tool for low voltage scanning electron microscopy (LVSEM) and providing new applications for Scanning Auger Microscopy (SAM) instruments.
本文展示了如何利用扫描电子显微镜(SEM)内进行的二次电子能谱(SEES),在低初级束电压下绘制样品原子序数图并获取体态价带态密度(DOS)信息。该技术使用电子能量分析器附件来检测散射二次电子(SE)谱形状的微小变化,并从中提取精细结构特征。对于六个不同的测试样品,实验和理论体态价带DOS分布之间取得了密切一致,归一化均方根偏差范围为2.7%至6.7%。此前似乎尚未报道过如此高的准确度水平。本文给出的结果表明,SEES将成为低电压扫描电子显微镜(LVSEM)的定量材料分析辅助工具,并为扫描俄歇显微镜(SAM)仪器提供新的应用。