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arXiv · 2312.11114

3D surface profilometry using neutral helium atoms

Aleksandar Radic·Sam M. Lambrick·Nick A. von Jeinsen·Andrew P. Jardine·David J. Ward
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Abstract

Three-dimensional mapping of surface structures is important in a wide range of biological, technological, healthcare and research applications, including taxonomy, microfluidics and fabrication. Neutral helium atom beams have been established as a sensitive probe of topography and have already enabled structural information to be obtained from delicate samples, where conventional probes would cause damage. Here, we demonstrate empirical reconstruction of a complete surface profile using measurements from a scanning helium microscope (SHeM), using the heliometric stereo method and a single detector instrument geometry. Results for the surface profile of tetrahedral aluminum potassium sulphate crystals demonstrate the areas of surfaces and facet orientations can be recovered to within 5% of the expected values.

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Aleksandar Radic, Sam M. Lambrick, Nick A. von Jeinsen, Andrew P. Jardine, David J. Ward. 2023-12-18. 3D surface profilometry using neutral helium atoms. https://doi.org/10.1063/5.0206374

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