We have developed a new depth-graded multilayer system comprising W and SiC layers, suitable for use as hard x-ray reflective coatings operating in the energy range 100–200 keV. Grazing-incidence x-ray reflectance at E = 8 keV was used to characterize the interface widths, as well as the temporal and thermal stability in both periodic and depth-graded W/SiC structures, whereas synchrotron radiation was used to measure the hard x-ray reflectance of a depth-graded multilayer designed specifically for use in the range E∼150–170 keV. We have modeled the hard x-ray reflectance using newly derived optical constants, which we determined from reflectance versus incidence angle measurements also made using synchrotron radiation, in the range E = 120–180 keV. We describe our experimental investigation in detail, compare the new W/SiC multilayers with both W/Si and W/B4C films that have been studied previously, and discuss the significance of these results with regard to the eventual development of a hard x-ray nuclear line telescope.
© 2003 Optical Society of America
Original Manuscript: August 11, 2002
Revised Manuscript: October 29, 2002
Published: May 1, 2003
David L. Windt, Soizik Donguy, Charles J. Hailey, Jason Koglin, Veijo Honkimaki, Eric Ziegler, Finn E. Christensen, Hubert Chen, Fiona A. Harrison, and William W. Craig, "W/SiC x-ray multilayers optimized for use above 100 keV," Appl. Opt. 42, 2415-2421 (2003)