A novel 3D absorption correction method for quantitative EDX-STEM tomography
A novel 3D absorption correction method for quantitative EDX-STEM tomography
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DOI：
10.1016/j.ultramic.2015.09.012
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发表时间：
2016-01-01
期刊：
影响因子：
2.2
通讯作者：
Midgley, P. A.
中科院分区：
文献类型：
--
作者：
Burdet, Pierre;Saghi, Z.;Midgley, P. A.
本文提出了一种新的三维方法来校正能量色散X射线（EDX）微量分析未知结构和成分的非均匀样品的吸收。通过使用基于STEM的断层扫描与EDX相结合，初始3D重建用于提取生成的X射线的位置以及通过样品到表面的X射线路径。然后逐个体素地计算检索所生成的X射线强度所需的吸收校正，估计X射线遇到的不同成分。该方法被应用于含有碳和氧的核/壳纳米线，这两种元素产生高度吸收的低能X射线。吸收被证明会导致主要的重建文物，在形式的不完全恢复的氧化物和错误的存在下的碳壳。通过应用校正方法，这些伪影大大减少。使用低吸收的参考X射线线评估该方法的准确度。(C)2015年，作者。由爱思唯尔公司出版。这是一篇开放获取的文章，使用CC BY许可证（http：//creativecommons.org/licenses/by/4.0/）。
This paper presents a novel 3D method to correct for absorption in energy dispersive X-ray (EDX) microanalysis of heterogeneous samples of unknown structure and composition. By using STEM-based tomography coupled with EDX, an initial 3D reconstruction is used to extract the location of generated X-rays as well as the X-ray path through the sample to the surface. The absorption correction needed to retrieve the generated X-ray intensity is then calculated voxel-by-voxel estimating the different compositions encountered by the X-ray. The method is applied to a core/shell nanowire containing carbon and oxygen, two elements generating highly absorbed low energy X-rays. Absorption is shown to cause major reconstruction artefacts, in the form of an incomplete recovery of the oxide and an erroneous presence of carbon in the shell. By applying the correction method, these artefacts are greatly reduced. The accuracy of the method is assessed using reference X-ray lines with low absorption. (C) 2015 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).