Journal article
Laser ablation of high-aspect-ratio hole arrays in tungsten for X-ray applications
National Centre for Nano Fabrication and Characterization, Technical University of Denmark1
Nanofabrication, National Centre for Nano Fabrication and Characterization, Technical University of Denmark2
Silicon Microtechnology, Nanofabrication, National Centre for Nano Fabrication and Characterization, Technical University of Denmark3
University of Copenhagen4
Department of Physics, Technical University of Denmark5
Neutrons and X-rays for Materials Physics, Department of Physics, Technical University of Denmark6
Periodic two-dimensional tungsten X-ray optical gratings were fabricated using a combination of pico-second laser ablation and wet chemical etch. A 200 μm thick cold-rolled sheet of tungsten (99.97%) was used as base material for the fabrication of a 1.5 × 1.5 cm2 periodic grating with an array of circular holes of approximately 12:1 aspect ratio.
The laser parameters were optimized to obtain through-hole diameters slightly smaller than the desired final dimension. Subsequent wet etching was used to precisely control the diameter of through-holes. The through-hole profile was characterized using scanning electron microscopy (SEM) and showed a slight conical shape with a slope of 1.3%.
The two-dimensional tungsten absorption grating was successfully tested in an X-ray phase-contrast imaging setup. The method has proven to have some relevant benefits, such as good reproducibility and fairly easy fabrication due to few manufacturing steps.
Language: | English |
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Year: | 2019 |
Pages: | 60-65 |
ISSN: | 18735568 and 01679317 |
Types: | Journal article |
DOI: | 10.1016/j.mee.2019.03.007 |
ORCIDs: | 0000-0001-9784-7504 , Silvestre, Chantal M. , Hansen, Ole and Hemmingsen, Jens H. |