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arXiv · 2105.03259

The modular Atom Probe Concept

Abstract

Atomic probe tomography (APT), based on the work of Erwin Mueller, is able to generate three-dimensional chemical maps in atomic resolution. The required instruments for APT have evolved over the last 20 years from an experimental to an established method of materials analysis. Here, we describe the realization of a new instrument concept that allows the direct attachment of APT to a dual beam SEM microscope with the main achievement of fast and direct sample transfer. New operational modes are enabled regarding sample geometry, alignment of tips and microelectrode. The instrument is optimized to handle cryo-samples at all stages of preparation and storage. The instrument comes with its own software for evaluation and reconstruction. The performance in terms of mass resolution, aperture angle, and detection efficiency is demonstrated with a few application examples.

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Patrick Stender, Helena Solodenko, Andreas Weigel, Irdi Balla, Tim Maximilian Schwarz, Jonas Ott, Manuel Roussell, Rüya Duran, Sebastian Eich, Mohammad Al-Shakran, Timo Jacob, Guido Schmitz. 2021-05-07. The modular Atom Probe Concept. https://arxiv.org/abs/2105.03259

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