Non-destructive depth reconstruction of Al-Al$_2$Cu layer structure with nanometer resolution using extreme ultraviolet coherence tomography

Johann Jakob Abel; Jonathan Apell; Felix Wiesner; Julius Reinhard; Martin Wünsche; Nadja Felde; Gabriele Schmidl; Jonathan Plentz; Gerhard G. Paulus; Stephanie Lippmann; Silvio Fuchs

arXiv · 2311.10743

Non-destructive depth reconstruction of Al-Al$_2$Cu layer structure with nanometer resolution using extreme ultraviolet coherence tomography

Johann Jakob Abel·Jonathan Apell·Felix Wiesner·Julius Reinhard·Martin Wünsche·Nadja Felde·Gabriele Schmidl·Jonathan Plentz·Gerhard G. Paulus·Stephanie Lippmann·Silvio Fuchs

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Abstract

Non-destructive cross-sectional characterization of materials systems with a resolution in the nanometer range and the ability to allow for time-resolved in-situ studies is of great importance in material science. Here, we present such a measurements method, extreme ultraviolet coherence tomography (XCT). The method is non-destructive during sample preparation as well as during the measurement, which is distinguished by a negligible thermal load as compared to electron microscopy methods. Laser-generated radiation in the extreme ultraviolet (XUV) and soft x-ray range is used for characterization. The measurement principle is interferometric and the signal evaluation is performed via an iterative Fourier analysis. The method is demonstrated on the metallic material system Al-Al$_2$Cu and compared to electron and atomic force microscopy measurements. We also present advanced reconstruction methods for XCT which even allow for the determination of the roughness of outer and inner interfaces.

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Johann Jakob Abel, Jonathan Apell, Felix Wiesner, Julius Reinhard, Martin Wünsche, Nadja Felde, Gabriele Schmidl, Jonathan Plentz, Gerhard G. Paulus, Stephanie Lippmann, Silvio Fuchs. 2023-10-29. Non-destructive depth reconstruction of Al-Al$_2$Cu layer structure with nanometer resolution using extreme ultraviolet coherence tomography. https://arxiv.org/abs/2311.10743

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