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arXiv · 2103.04765

Development of an energy-sensitive detector for the Atom Probe Tomography

Abstract

A position-energy-sensitive detector has been developed for APT instruments in order to deal with some mass peak overlap issues encountered in APT experiments. Through this new type of detector, quantitative and qualitative improvements could be considered for critical materials introducing mass peak overlaps, such as nitrogen and silicon in TiSiN systems, or titanium and carbon in cemented carbide materials. This new detector is based on a thin carbon foil positioned on the front panel of a conventional MCP-DLD detector. According to several studies, it has been demonstrated that the impact of ions on thin carbon foils has the effect of generating a number of transmitted and reflected secondary electrons that mainly depends on both the kinetic energy and the mass of incident particles. Despite the fact that this phenomenon is well known and has been widely discussed for decades, no studies have been performed to date for using it as a mean to discriminate particles energy. Therefore, this study introduces the first experiments on a potential new generation of APT detectors that would be able to resolve mass peak overlaps through the energy-sensitivity of thin carbon foils.

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Christian Bacchi, Gérald Da Costa, Emmanuel Cadel, Fabien Cuvilly, Jonathan Houard, Charly Vaudolon, Antoine Normand, François Vurpillot. 2021-03-08. Development of an energy-sensitive detector for the Atom Probe Tomography. https://doi.org/10.1017/s1431927621012708

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