7th EUV-FEL Workshop

Tsukuba Campus - Kobayashi Hall (Kenkyu-Honkan Building) (KEK)

Tsukuba Campus - Kobayashi Hall (Kenkyu-Honkan Building)


1-1 Oho Tsukuba, Ibaraki  305-0801 Japan.
Hiroshi KAWATA (KEK)

Announcement of the 7th EUV-FEL Workshop!

Utilization of IoT, AI and related technologies, information processing devices and systems are evolving towards an ultra-smart society. To this end, EUV exposure technology has been introduced in leading-edge semiconductor chip production.          

If we scope future EUV lithography technologies such as high NA EUV lithography exposure system, it is important to increase the EUV light source power to reduce the stochastic effect by means of the shot noise and also to take into account reducing the production cost in order to keep Sustainable Semiconductor Technology and Science. Indeed, in the IRDS report of 2022 on Lithography, both are described for future lithography (https://irds.ieee.org/editions/2022/irds%E2%84%A2-2022-lithography). Furthermore, there is another description of Beyond EUVL in a roadmap timetable in the report. These challenges may be solved by EUV-FEL which is a high-power and wavelength-tunable EUV light source.

The workshop will be held in the afternoon on 30 January 2023 as an international meeting in English. The workshop site will be both at Kobayashi-hall in KEK and on Zoom system.    Dr. Harry Levinson (HJL Lithography) will give a keynote lectures about “Free-electron lasers and the future of EUV lithography”.  In addition, the other invited speakers are Prof. Takeo Watanabe (University of Hyogo), Prof. Takahiro Kozawa (Osaka University), Dr. Seiji Nagahara (Tokyo Electron Ltd.) and Prof. Norio Nakamura (KEK).     
After the scientific session, we will have a site tour at cERL (compact Energy Recovery Linac) and STF (Superconducting RF Test Facility) in KEK, so that you can look at the real accelerator test facilities towards to the EUV-FEL.         

We hope that many people will participate and discuss on high-power EUV light sources for the future at the meeting.    

Sunao Ishihara
Representative of EUV-FEL Light Source Industrialization Study Group for Industrialization 

Hiroshi Kawata
High Energy Accelerator Research Organization, Innovation Center for Applied Superconducting Accelerator (iCASA)


This workshop is supported by funding based on "KEK Donation Programs".

    • Opening remarks
      Convener: Sunao Ishihara (Representative of EUV-FEL Light Source Study Group for Industrialization)
    • Target of the workshop
      Convener: Hiroshi Kawata (Secretary of the Workshop)
    • 1
      Free-electron lasers and the future of EUV lithography

      In order to contain photon shot-noise and the resulting process variations and defects, high power light sources will be needed to extend EUV lithography. Moreover, efficient control of polarization will be required to maximize optical contrast at high numerical apertures (NA). Similarly, EUV lithography at a wavelength shorter than 13.5 nm will require alternatives to tin-based laser-produced plasma (LPP) light sources. Free-electron lasers (FELs) have the potential to address all of these issues. However, to be suitable as light sources for semiconductor R&D and high volume manufacturing, issues such as reliability and flexibility will need to be addressed. In addition to factors related to the light source, there are other issues that will limit the extension of EUV lithography. Many limiting factors involve imaging materials, such as resists. Because of mask 3D effects, new mask materials may be required, and computational lithography for high-NA EUV will be very complex. Solutions for these additional issues will be needed to enable fully the nodes at which FEL’s would be used as EUV light sources.

      Harry J. Levinson is currently an independent lithography consultant. He spent most of his career working in the field of lithography at several companies – AMD, Sierra Semiconductor, IBM, and GlobalFoundries. Levinson served for several years as the chairman of the USA Lithography Technology Working Group that participated in the generation of the lithography chapter of the International Technology Roadmap for Semiconductors. He has published numerous articles on lithographic science and is the author of three books on lithography. He holds over 70 US patents. Levinson is an SPIE Fellow, previously chaired the SPIE Publications Committee, and served on SPIE’s Board of Directors. In recognition of his contributions to SPIE, he received the Society’s 2014 Directors’ Award. In 2022 he received the SPIE Frits Zernike Award in Microlithography. Levinson has a Ph.D. in physics from the University of Pennsylvania. His Ph.D. thesis, titled “Resonances and Collective Effects in Photoemission,” addressed certain phenomena involving the interactions of light and matter. For this work, he received the Wayne B. Nottingham Prize in surface science.

      Speaker: Harry J. Levinson (HJL Lithography)
    • 2
      Technical issue of EUVL and prospect for EUVL and Beyond EUVL
      Speaker: Takeo Watanabe (University of Hyogo)
    • 2:30 PM
    • 3
      Present state of the EUV-FEL light source for future lithography
      Speaker: Norio Nakamura (KEK)
    • 4
      Current status and prospect of extreme ultraviolet resists
      Speaker: Takahiro Kozawa (Osaka University)
    • 5
      TEL's Patterning Approaches Toward High NA EUV Lithography
      Speaker: Seiji Nagahara (Tokyo Electron Ltd.)
    • Final session
      Convener: Hiroshi Kawata (Secretary of the Workshop)
    • Closing address
      Convener: Shin-ichi Adachi (KEK)