Fabrication of High-aspect-ratio Hard X-ray Zone Plates withHSQ Plating Molds

摘要

Fresnel zone plates are important x-ray diffractive optics which offer a focusing resolution approaching thetheoretical limit. In hard x-ray region, the refractive indices of all the materials are close to unity, which requeststhick zone plate to achieve a reasonable efficiency. It makes high-resolution zone plate extremely difficult tofabricate due to its high aspect ratio. We report a LIGA-like fabrication process employing e-beam resist HSQas the plating mold material, which is relative simply compared with traditional processes. 1-μm-thick gold zoneplates with 80-nm-wide outermost zone have been fabricated with this process