LAUSR

Full-field X-ray microscopes are extremely powerful and, in contrast to scanning-type X-ray microscopes and coherent diffraction imaging, capable of imaging objects without the need for sample scanning and complex data analysis. Thus, they are compatible with real-time observation and spectronanoscopy. The performance of this type of microscope is strongly dependent on the characteristics and quality of the imaging optics used. Fresnel zone plates (FZPs), the most important imaging optics at the X-ray region, enable high-resolution imaging. However, general FZPs are barely capable of focusing/imaging X-rays with energy greater than 15 keV since the diffraction efficiency tends to decrease with increase in the X-ray energy. High-energy X-rays, though, are extremely useful for imaging the interior of thick samples, such as semiconductor devices and complex materials. One imaging optics compatible with such X-rays is a multilayer imaging mirror. Out of the available X-ray mirrors, advanced Kirkpatrick-Baez mirror (AKB) optics is a realistic solution for high resolution because of the possibility of mirror fabrication with a shape accuracy of a few nanometers. In this work, we have developed and demonstrated AKB optics comprising four multilayer mirrors (Fig. 1).