Construction of superconducting bulk magnet magnetron sputtering apparatus for fabrication of highly reflective optical mirrors

Uichiro Mizutani, Takashi Yamaguchi, Hiroshi Ikuta, Tetsuya Tomofuji, Yosuke Yanagi, Yoshitaka Itoh, Tetsuo Oka

Research output: Contribution to journalArticle

2 Citations (Scopus)


We have developed the two-cathode magnetron sputtering apparatus equipped with superconducting permanent magnet to produce Mo/Si multi-layer films, which would potentially serve as a high-quality optical mirror at extreme ultraviolet (EUV) wavelength of 13.5 nm. The best deposition condition was searched by analyzing the structure of the inter-diffusion layer formed in the Mo/Si bi-layer film prepared under different deposition conditions. It was found that (1) Xe gas should be used as inert gas species, (2) its pressure is lower than 4 × 10-2 Pa, (3) a throw distance is longer than 250 mm and (4) discharge voltage around 2 kV. By making full use of these data, we synthesized Mo/Si multi-layer films and analyzed the structure and its effect on the reflectivity. The highest EUV-reflectivity so far obtained is 67% in the normal incident condition.

Original languageEnglish
Pages (from-to)84-89
Number of pages6
JournalMaterials Science and Engineering B: Solid-State Materials for Advanced Technology
Issue number1
Publication statusPublished - 2008 Jun 15



  • EUV-lithography
  • Magnetron sputtering
  • Optical mirror
  • Superconducting permanent magnet

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

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