FABRICATION OF A HARD X-RAY SPUTTERED-SLICED FRESNEL PHASE ZONE-PLATE

A Fresnel phase zone plate for hard x ray was fabricated by physical v apor deposition alternating transparent and opaque layers onto a fine gold wire core 47 mu m in diameter. The zone plate, which is comprised of 25 pairs of alternating Ag and C layers, is designed to operate wi th a focal length of 124 mm for a parallel beam at 8.1 keV. The thickn ess of the zone plate is less than 10 mu m and is capable of operating as a phase zone plate, Using the brilliant monochromatized x-ray beam from the TRISTAN Main Ring, with an undulator, the minimum focal spot size attained for the first order focal beam was 0.5 mu m phi. The li ght collecting efficiency was determined to be near 11%. (C) 1997 Amer ican Institute of Physics.