Alloy–ceramic oxide multilayers of Ni<sub>80</sub>Nb<sub>20</sub>– MgO with 3.56-nm period have been made by use of the pulsed-laser deposition technique and characterized by means of grazing-incidence x-ray reflectivity. The interface roughness was found to be only ~0.35 nm at the two interfaces, Ni<sub>80</sub>Nb<sub>20</sub>– MgO and MgO–Ni<sub>80</sub>Nb<sub>20</sub>, leading to a peak reflectivity of ~38% at the first order. The atomic structure in the two individual layers, Ni<sub>80</sub>Nb<sub>20</sub> and MgO, is found to be amorphous, in agreement with the deposition conditions. These multilayers can be used as mirrors for soft x rays in the angular range 18° to 39°, depending on the actual wavelength of radiation in the water-window region.
© 2001 Optical Society of America
Satish Vitta, Martin Weisheit, Thorsten Scharf, and H.-U. Krebs, "Alloy-ceramic oxide multilayer mirrors for water-window soft x rays," Opt. Lett. 26, 1448-1450 (2001)