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arXiv · 2402.12082

X-ray multibeam ptychography at up to 20 keV: nano-lithography enhances X-ray nano-imaging

Abstract

Non-destructive nano-imaging of the internal structure of solid matter is only feasible using hard X-rays due to their high penetration. The highest resolution images are achieved at synchrotron radiation sources (SRF), offering superior spectral brightness and enabling methods such as X-ray ptychography delivering single-digit nm resolution. However the resolution or field of view is ultimately constrained by the available coherent flux. To address this, the beam's incoherent fraction can be exploited using multiple parallel beams in an approach known as X-ray multibeam ptychography (MBP). This expands the domain of X-ray ptychography to larger samples or more rapid measurements. Both qualities favor the study of complex composite or functional samples, such as catalysts, energy materials, or electronic devices. The challenges of performing ptychography at high energy and with many parallel beams must be overcome to extract the full advantages for extended samples while minimizing beam attenuation. Here, we report the application of MBP with up to 12 beams and at photon energies of 13 and 20 keV. We demonstrate performance for various samples: a Siemens star test pattern, a porous Ni/\ce{Al2O3} catalyst, a microchip, and gold nano-crystal clusters, exceeding the measurement limits of conventional hard X-ray ptychography without compromising image quality.

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Tang Li, Maik Kahnt, Thomas L. Sheppard, Runqing Yang, Ken Vidar Falch, Roman Zvagelsky, Pablo Villanueva-Perez, Martin Wegener, Mikhail Lyubomirskiy. 2024-02-19. X-ray multibeam ptychography at up to 20 keV: nano-lithography enhances X-ray nano-imaging. https://arxiv.org/abs/2402.12082

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