Kazuya Saitoh

Characterization of sliced multilayer zone plates for hard x rays (invited)

Circular zone plates for hard x rays, fabricated by dc planar magnetron sputtering, have been characterized using monochromatized synchroton x rays. The zone plates consisted of either 5 or 20 pairs of altenating WSi2 and C layers. The minimum focal spot size attained was less than 3 μm× 10 μm in the vertical and horizontal directions, respectively. The efficiency of the zone plate with 20 layer pairs was determined to be about 4.5%. An x‐ray transmission image of a No. 2000 mesh Cu grid and an x‐ray fluorescence image of a patterned Co thin film were measured, and it was demonstrated that a high‐resolution image could be obtained with the present zone plate. The possibility of implementing the phase zone plate in hard x‐ray range is considered.

Fabrication and Characterization of Multilayer Zone Plate for Hard X-Rays

A zone plate for 8 keV X-rays with alternative WSi2 and C layers was fabricated using a DC planer magnetron sputtering. The zone plate had 20 pairs of a high aspect ratio for hard X-rays. Its thickness was about 50 µm. An X-ray interference pattern through the zone plate was observed using monochromated synchrotron X-rays, and a focusing property of the zone plate was confirmed. The focal length was about 67 mm and the spot size (FWHM) was smaller than 8 µm.