Target Design in SEM-Based Nano-CT and Its Influence on X-ray Imaging
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Published:2023-08-04
Issue:8
Volume:9
Page:157
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ISSN:2313-433X
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Container-title:Journal of Imaging
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language:en
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Short-container-title:J. Imaging
Author:
Fell Jonas1ORCID, Wetzler Felix1, Maisl Michael2, Herrmann Hans-Georg12ORCID
Affiliation:
1. Lightweight Systems, Department of Materials Science, Campus E3 1, Saarland University, 66123 Saarbrücken, Germany 2. Fraunhofer Institute for Nondestructive Testing IZFP, Campus E3 1, 66123 Saarbrücken, Germany
Abstract
Nano-computed tomography (nano-CT) based on scanning electron microscopy (SEM) is utilized for multimodal material characterization in one instrument. Since SEM-based CT uses geometrical magnification, X-ray targets can be adapted without any further changes to the system. This allows for designing targets with varying geometry and chemical composition to influence the X-ray focal spot, intensity and energy distribution with the aim to enhance the image quality. In this paper, three different target geometries with a varying volume are presented: bulk, foil and needle target. Based on the analyzed electron beam properties and X-ray beam path, the influence of the different target designs on X-ray imaging is investigated. With the obtained information, three targets for different applications are recommended. A platinum (Pt) bulk target tilted by 25° as an optimal combination of high photon flux and spatial resolution is used for fast CT scans and the investigation of high-absorbing or large sample volumes. To image low-absorbing materials, e.g., polymers or organic materials, a target material with a characteristic line energy right above the detector energy threshold is recommended. In the case of the observed system, we used a 30° tilted chromium (Cr) target, leading to a higher image contrast. To reach a maximum spatial resolution of about 100 nm, we recommend a tungsten (W) needle target with a tip diameter of about 100 nm.
Funder
German Research Council
Subject
Electrical and Electronic Engineering,Computer Graphics and Computer-Aided Design,Computer Vision and Pattern Recognition,Radiology, Nuclear Medicine and imaging
Reference21 articles.
1. Lutter, F., Dremel, K., Engel, J., Althoff, D., Zabler, S., Westphal, N., and Hanke, R. (2019, January 2–4). XRM-II nanoCT–SEM based computed tomography. Proceedings of the International Symposium on Digital Industrial Radiology and Computed Tomography, Fürth, Germany. 2. Combining X-ray Nano Tomography with focused ion beam serial section imaging—Application of correlative tomography to integrated circuits;Lutter;Nucl. Instrum. Methods Phys. Res. Sect. B Beam Interact. Mater. At.,2021 3. Engstler, M., Fell, J., Lutter, F., Maisl, M., Herrmann, H.G., and Mücklich, F. (2020, January 4–7). Correlative Tomography–Combining X-ray Nanotomography and FIB/SEM Serial Sectioning to analyze Al-Si cast alloys. Proceedings of the 10th International Conference on Industrial Computed Tomography, Wels, Austria. 4. A FIB-SEM Based Correlative Methodology for X-Ray Nanotomography and Secondary Ion Mass Spectrometry: An Application Example in Lithium Batteries Research;Cressa;Microsc. Microanal.,2022 5. Three-dimensional imaging of microstructural evolution in SEM-based nano-CT;Fell;Tomogr. Mater. Struct.,2023
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