Sub‐micrometre focusing of intense 100 keV X‐rays with multilayer reflective optics

• Published in: Journal of synchrotron radiation Vol. 31; no. 2; pp. 276 - 281
• Main Authors: Koyama, Takahisa, Yumoto, Hirokatsu, Miura, Takanori, Matsuzaki, Yasuhisa, Yabashi, Makina, Ohashi, Haruhiko
• Format: Journal Article
• Language: English
• Published: 5 Abbey Square, Chester, Cheshire CH1 2HU, England International Union of Crystallography 01.03.2024; John Wiley & Sons, Inc
• Subjects: 100 keV X‐rays; Astronomy; Focusing; high-energy x-rays; Ion beams; Light sources; multilayer focusing mirrors; multilayer monochromators; Multilayers; Photons; Research Papers; scanning transmission imaging; Tantalum; 100 keV X-rays; scanning transmission imaging; multilayer focusing mirrors; multilayer monochromators; high-energy X-rays
• ISSN: 1600-5775; 0909-0495; 1600-5775
• DOI: 10.1107/S1600577524000213

A high‐flux sub‐micrometre focusing system was constructed using multilayer focusing mirrors in Kirkpatrick–Baez geometry for 100 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 100 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 0.32 µm (V) × 5.3 µm (H) with a flux of 1 × 1012 photons s−1. However, when a limited horizontal slit was used to form a secondary source, the focusing beam size decreased to 0.25 µm (V) × 0.26 µm (H) with a flux of 6 × 1010 photons s−1. The 200 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 100 keV focusing system is applicable to various fields of nondestructive analyses with sub‐micrometre resolutions. A high‐flux sub‐micrometre focusing system for 100 keV X‐rays using multilayer focusing mirrors was constructed and evaluated at the undulator beamline BL05XU of SPring‐8.