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arXiv · 1810.12129

Towards Sub-micrometer High Aspect Ratio X-ray Gratings by Atomic Layer Deposition of Iridium

Joan Vila-Comamala·Lucia Romano·Vitaliy Guzenko·Matias Kagias·Marco Stampanoni·Konstantins Jefimovs
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Abstract

X-ray grating interferometry is an excellent technique for X-ray phase contrast imaging and X-ray wavefront sensing with applications in materials science, biology and medical diagnosis. Among other requirements, the method depends on the availability of highly X-ray absorbing metallic gratings. Here, we report on the fabrication and characterization of high aspect ratio iridium gratings with a period of one micrometer and a depth of 30 micrometer combining deep reactive ion etching of silicon and atomic layer deposition of iridium. The implementation of such structures can greatly enhance the sensitivity of grating-based X-ray phase contrast imaging and thus, expand further its broad range of applications.

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Joan Vila-Comamala, Lucia Romano, Vitaliy Guzenko, Matias Kagias, Marco Stampanoni, Konstantins Jefimovs. 2018-10-29. Towards Sub-micrometer High Aspect Ratio X-ray Gratings by Atomic Layer Deposition of Iridium. https://doi.org/10.1016/j.mee.2018.01.027

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