14.5% near-normal incidence reflectance of Cr/Sc x-ray multilayer mirrors for the water window
2003 (English)In: Optics Letters, ISSN 0146-9592, Vol. 28, no 24, 2494-2496 p.Article in journal (Refereed) Published
Cr/Sc multilayer mirrors, synthesized by ion-assisted magnetron sputter deposition, are proved to have a high near-normal reflectivity of R = 14.5% at a grazing angle of 87.5degrees measured at the wavelength A = 3.11 nm, which is an improvement of more than 31% compared with previously published results. Elastic recoil detection analyses show that the mirrors contained as much as 15 at. % of N and traces of C and O. Soft x-ray reflectivity simulations reveal interface widths of sigma = 0.34 nm and an exceptionally small layer thickness drift of similar to1.6 X 10(-5) nm/multilayer period throughout the stack. Simulations show that a reflectivity of R = 25.6% is attainable if impurities and layer thickness drift can be eliminated. The abrupt interfaces are achieved with ion assistance with a low ion energy of 24 eV and high ion-to-metal flux ratios of 7.1 and 23.1 during Cr and Se sputter deposition, respectively. In addition, a near-normal incidence reflectivity of 5.5% for the C VI emission line (lambda = 3.374 nm) from a laser plasma source was verified. (C) 2003 Optical Society of America.
Place, publisher, year, edition, pages
2003. Vol. 28, no 24, 2494-2496 p.
National CategoryEngineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-48449OAI: oai:DiVA.org:liu-48449DiVA: diva2:269345