Fabrication of X-ray absorption grating for X-ray Talbot interferometry by ultracentrifugal deposition

We fabricated a 9 μm-pitch X-ray absorption grating using ultracentrifugal deposition, a fast and simple technique for producing high-aspect-ratio structures. A silicon mold was prepared via deep reactive ion etching and filled with platinum (Pt) particles in approximately one hour. The fabricated grating was evaluated through cross-sectional scanning electron microscopy (SEM) and X-ray Talbot interferometry using a synchrotron X-ray beam. SEM analysis revealed a nominal Pt thickness of 47.1 μm, while interferometric measurements indicated an effective thickness of 26 μm, corresponding to a 55% filling ratio. Phase-contrast, differential-phase, and dark-field (visibility-contrast) images of a polyoxymethylene (POM) sphere were successfully obtained using the grating, demonstrating sufficient image quality and practical applicability. This method has the potential to be a scalable alternative to traditional techniques for fabricating fine-pitch X-ray gratings.