High-pressure plasma etching up to 9 atm toward uniform processing inside narrow grooves of high-precision X-ray crystal optics

• Published in: Applied physics express Vol. 17; no. 1; pp. 16001 - 16005
• Main Authors: Matsumura, Shotaro, Ogasahara, Iori, Miyake, Masafumi, Osaka, Taito, Toh, Daisetsu, Yamada, Jumpei, Yabashi, Makina, Yamauchi, Kazuto, Sano, Yasuhisa
• Format: Journal Article
• Language: English
• Published: IOP Publishing 01.01.2024
• Subjects: plasma etching; precision engineering; X-ray crystal optics
• ISSN: 1882-0778; 1882-0786
• DOI: 10.35848/1882-0786/ad119a

Abstract We developed a new etching technique using plasma generated at high pressure up to 9 atm. Operating at 9-atm pressure with a 30- μ m-diameter wire electrode, we demonstrated the generation of well-ordered plasma at a narrow gap of ∼10 μ m between the electrode and workpiece, and realized a high spatial resolution of <40 μ m during processing. This technique should allow for the processing of high-precision X-ray crystal optical devices with compact and complex structures, such as a micro channel-cut crystal monochromator with an extremely narrow (sub-100 μ m width) groove for realization of Fourier-transform-limited X-ray lasers with high intensity.