Elliptical multilayer Bragg-Fresnel lenses with submicron spatial resolution for X-rays

Elliptical Bragg-Fresnel multilayer lenses (BFML), designed and fabricated at the Institute of Microelectronic Technology (Russian Academy of Science) have been used for two-dimensional focusing of the white X-ray synchrotron beam at LURE (Orsay France). For two fixed beam energies (8 keV and 12.4 keV), the spot size produced was approximately 1 μm as determined from a high resolution photographic plate. A fluorescence X-ray scanning microprobe based on these BFML lenses was also tested. The transmitted signal registered during the scan of a test object shows less than 1 μm resolution with 8 keV output photon energy. 2D scanning images with submicron resolution of test objects in transmission mode at 8 keV and 12.4 keV beam energies are presented.