Fabrication of multiple slit using stacked-sliced method for hard X-ray Talbot-Lau interferometer

We propose using a multiple slit fabricated by a simple and economical stacked-sliced method for X-ray phase imaging with a Talbot-Lau X-ray interferometer. Foils of Ta and Al were stacked alternately, and the stack was sliced up perpendicular to the stacking direction. We successfully fabricated a hard X-ray multiple slit with a space size (Al foil thickness) of about 10μm and an aspect ratio of 60. Optical microscopy evaluation showed its regular pitch pattern at its surface. A high-resolution X-ray transmission image proved the regularity of the inner part. The visibility of moiré fringes and the phase-contrast image obtained using the Talbot-Lau interferometer with the multiple slit proved the feasibility of the stacked-sliced approach.