RESUMEN
A high-flux sub-micrometre focusing system was constructed using multilayer focusing mirrors in Kirkpatrick-Baez geometry for 100â keV X-rays. The focusing mirror system had a wide bandwidth of 5% and a high peak reflectivity of 74%. Performance was evaluated at the undulator beamline BL05XU of SPring-8, which produced an intense 100â keV X-ray beam with a bandwidth of 1%. When the light source was focused directly in both vertical and horizontal directions, the beam size was measured to be 0.32â µm (V) × 5.3â µm (H) with a flux of 1 × 1012â photonsâ s-1. However, when a limited horizontal slit was used to form a secondary source, the focusing beam size decreased to 0.25â µm (V) × 0.26â µm (H) with a flux of 6 × 1010â photonsâ s-1. The 200â nm line and space patterns of a Siemens star chart made of tantalum were clearly resolved by the absorption contrast of the focused beam. This 100â keV focusing system is applicable to various fields of nondestructive analyses with sub-micrometre resolutions.