Design and Fabrication of Broad Angular Response Supermirrorfor Hard X-Ray Optics

Abstract

A broad angular response supermirror is designed by the simplexoptimization method and fabricated by dc magnetron sputtering. Thenegative effect of the interfacial imperfection, mainly consulting frominterface roughness and diffusion, is emerged in the calculation of theprecise performance of the supermirror. The reflectivity of such asupermirror is measured by the x-ray diffraction instrument (XRD) at CuKα line (λ = 0.154 nm). The experimental reflectivity is about 30%in a fixed broad grazing incident angular range(0.55°–0.85°). The fitting data prove that the thicknessof each layer, which is larger than the prospect 0.5 nm, is differentfrom the designed one and the roughness in the supermirror is about0.85 nm.