RESUMO
Alloy-ceramic oxide multilayers of Ni(80)Nb(20)- 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(80)Nb(20)- MgO and MgO-Ni(80)Nb(20), leading to a peak reflectivity of ~38% at the first order. The atomic structure in the two individual layers, Ni(80)Nb(20) 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 degrees to 39 degrees , depending on the actual wavelength of radiation in the water-window region.
RESUMO
Multilayers for the water window region of the soft x rays have been prepared by pulsed laser ablation with amorphous Ni(50) Nb(50) and amorphous C. The structural characterization of the multilayers, period d = 2.41 nm, shows that the interfaces are sharp with a roughness of only 0.4 nm that is chemical, not morphological, in origin. The interface roughness was found to be uncorrelated in the direction normal to the plane of the film. The normal incidence soft-x-ray reflectivity of the multilayer at 4.85-nm wavelength is 0.06%, 1 order of magnitude lower than the theoretically predicted value. However, the resolution limit lambda/Dlambda of the multilayer was found to be 16.7, close to the theoretically predicted value.
