title: Development of multilayer laminar-type diffraction gratings to achieve high diffraction efficiencies in the 1-8 keV energy region.
abstract: W/C and Co/SiO(2) multilayer gratings have been fabricated by depositing a multilayer coating on the surface of laminar-type holographic master gratings. The diffraction efficiency was measured by reflectometers in the energy region of 0.6-8.0 keV at synchrotron radiation facilities as well as with an x-ray diffractometer at 8.05 keV. The Co/SiO(2) and W/C multilayer gratings showed peak diffraction efficiencies of 0.47 and 0.38 at 6.0 and 8.0 keV, respectively. To our knowledge, the peak efficiency of the W/C multilayer grating is the highest measured with hard x rays. The diffraction efficiency of the Co/SiO(2) multilayer gratings was higher than that of the W/C multilayer grating in the energy range of 2.5-6.0 keV. However, it decreased significantly in the energy above the K absorption edge of Co (7.71 keV). For the Co/SiO(2) multilayer grating, the measured diffraction efficiencies agreed with the calculated curves assuming a rms roughness of approximately 1 nm.
authors.affiliation: Quantum Beam Science Directorate, Japan Atomic Energy Agency, Kizu, Kyoto, Japan. ishino.masahiko@jaea.go.jp
authors.forename: Masahiko
authors.initials: M
authors.lastname: Ishino
authors.forename: Philip A
authors.initials: PA
authors.lastname: Heimann
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Sasai
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Hatayama
authors.forename: Hisataka
authors.initials: H
authors.lastname: Takenaka
authors.forename: Kazuo
authors.initials: K
authors.lastname: Sano
authors.forename: Eric M
authors.initials: EM
authors.lastname: Gullikson
authors.forename: Masato
authors.initials: M
authors.lastname: Koike