Blue-X

Blue-X Technical Progress Presented at SPIE Advanced Lithography 

“Future of EUV” Special Session 

It was an honor to present the Blue-X Technical Working Group (TWG) organization and technical progress at a very well-attended Future of EUV special session during SPIE Advanced Lithography 2026 in San Jose. The presentation outlined Blue-X as an industry-wide initiative exploring wavelength reduction (2–7 nm range) as a complementary path to extending Moore’s Law beyond High-NA EUV.

The talk began by positioning the Blue-X approach relative to proposals for increasing numerical aperture beyond High-NA EUV. By selecting a wavelength of 3.1 nm and an NA of 0.27, we demonstrated that a depth of focus of ~43 nm and k₁ ≈ 0.6 can be achieved for resolving 7 nm half-pitch metal nodes projected for the mid-2030s. Unlike Hyper-NA, which faces increasing challenges in depth of focus, mask 3D effects, and cost of ownership, Blue-X leverages wavelength scaling—historically the primary driver of lithographic advancement.

The Blue-X TWG consortium now includes more than 75 member organizations and over 220 assignees representing chip makers, OEMs, national laboratories, universities, and consultants. Eleven sub-TWGs, led by recognized technology leaders, are actively evaluating optics, plasma and FEL photon sources, resist and patterning, masks, optical constants, and scanner design. The initial focus on resist exposure at 6.7 nm has shifted to 3.1 nm, with ongoing resist evaluations at Berkeley Lab and planned open-frame and interference lithography exposures at PSI beginning mid-2026.

Key technical highlights included:

  • Multilayer (ML) optics in the water window region, with Sc/Cr at 3.127 nm selected as the current working baseline.
  • Strategies to improve ML reflectivity from ~40% today toward 55–60% through interface control and roughness reduction.
  • Plasma source modeling (Ga and Sc) and FEL development efforts, including tunable 2–7 nm capability with narrow bandwidth and reduced out-of-band radiation.
  • 6.7 nm resist dose-to-clear values primarily in the 50–150 mJ/cm² range.
  • Flare control and MSFR requirements (~20 pm range) for 3.1 nm optics.
  • Four proposed paths to reduce stochastics at shorter wavelengths:
    1. Three-beam lithography (IBM)
    2. Larger masks (12-inch, 8×) (IBM)
    3. Dose partitioning
    4. Image contrast enhancement inspired by soft X-ray microscopy techniques

Throughput modeling shows that with improving ML reflectivity and modest architectural changes (e.g., reduced reflections at
lower NA), a Blue-X micro-exposure tool (MET) becomes feasible within a 3–5 year horizon.

The central message is clear: moving from 13.5 nm to 3.1 nm is not the introduction of a fundamentally new technology stack, but rather a challenging and systematic upgrade building upon the physics, infrastructure, and lessons learned from 193 nm to EUVL. Blue-X represents a coordinated, pre-competitive industry effort to explore this next wavelength node responsibly and collaboratively.

If you are not yet part of the Blue-X Technical Working Group, now is the time to engage.

For more information or to request the Blue-X white paper, contact: info@euvlitho.com

You can view the presentation here.

 Blue-X TWG January 2026 Update

Program Highlights and Updates

The new Blue-X TWG White Paper (January 2026 edition) has been published and is now available to existing Blue-X TWG members on the internal homepage. Organizations interested in learning more about Blue-X TWG and potential membership are encouraged to contact us at admin@euvlitho.com.

At the December all-sub-TWG meeting, members reviewed progress across a wide range of technical activities. Updates were presented on overall resist efforts, roadmaps, optical design, plasma, resist, and metrology. The meeting also included a technical update on the Flying Circus Metrology program, along with source development presentations from Research Instruments and Advanced Fusion Services (AFS). Two invited speakers, from DESY (Germany) and Lawrence Berkeley National Laboratory (LBL), shared perspectives aligned with the group’s objectives. The group also welcomed a new member, Tekscend, who introduced their company and technical capabilities.

On the technical front, Blue-X has initiated resist exposure studies in the water window region at CXRO. A wavelength has been selected for these studies. Following scheduled beamline upgrades at CXRO, the team plans to continue this work at PSI later this summer. In January, the Plasma Source sub-TWG met and selected two elements for further experimental and modeling studies to evaluate their suitability for water window source development. The Mask sub-TWG also met to define next steps, with multilayer (ML) development continuing. The Plasma Source, Mask, ML, and Resist sub-TWG groups will meet again in March 2026 via Zoom. The next all-sub-TWG meeting is scheduled for March 31 at 8:00 AM CST (Zoom).

Looking ahead, Blue-X members will present new technical results at the 2026 SPIE Advanced Lithography Conference (February 23, 26, 2026) related to advanced lithography at wavelengths below 13.5 nm. Notably, in Sessions 6 and 7 on “Future of EUV,” six of the eight papers will be presented by Blue-X TWG members, highlighting the group’s continued leadership in next-generation EUV technology.

 Blue-X TWG Year 2 Update (November 2025)

Blue-X TWG is pleased to begin Year 2 and to share the latest program progress. We continue to advance collaborative research that supports next-generation lithography at wavelengths below 13.5 nm. Blue-X TWG member dues are actively supporting collaborative projects at CXRO, guided by the respective Sub-TWGs. Recent activities include a beamline shift in October for 6.7 nm resist exposures, with additional exposures scheduled in December in partnership with commercial resist suppliers. Discussions on multilayer development, optical quality requirements and plasma source development in the water-window region are advancing and helping shape the next steps for the program.

We also welcome new organizations to the Blue-X TWG, including the University of California, San Diego (UCSD) and Research Instrumentations Corporation, along with AGC, Photronics, and Osaka University, all of which have joined in the past three months. Our membership now includes more than seventy organizations and over two hundred ten representatives who are collectively supporting research on plasma sources operating below 13.5 nm.

Upcoming: December 11 resist exposures at CXRO at 6.7 nm and in the water-window region, Plasma Sub-TWG meeting on December 4, and All Sub-TWG meeting on December 16. Meetings are open to all Blue-X TWG members. 

Annual All Sub-TWG Meeting (September 30, 2025)

Annual All Sub-TWG Meeting will be held on Tuesday, September 30, 2025, at 8:00 AM US Central Time (Zoom).

This year’s meeting will be a special one as we:

  • Celebrate the successful completion of Year 1
  • Share a summary of achievements and status for Blue-X TWG and sub-TWGs
  • Present plans for Year 2 and beyond
  • Hear detailed technical updates and presentations from sub-TWGs
  • Welcome three new members (Asahi Glass, Osaka University, and Photronics) to the Blue-X community
  • Final Agenda

Key Updates from Blue – X TWG (August – September 2025)

Blue – X TWG members are at the forefront of technological advancement, spearheading efforts in next-generation lithography at sub-13.5 nm to further extend Moore’s Law.

In August and September, there have been several updates regarding scheduled meetings among Sub-TWGs, including Resist, Mask, Optical Design and Imaging, ML Optics, as well as specialized sub-groups such as Plasma Sources and Atomic Data & Modeling. The Resist Sub-TWG convened on August 12th, and additional Sub-TWG meetings are planned throughout September. A quarterly meeting for all Blue – X Sub-TWGs will take place on September 30th, where teams will present progress summaries and highlights from Blue – X TWG’s inaugural year. Participation and ongoing updates are available exclusively to Blue – X TWG members.

Technical Highlights

Recent developments from the various sub-TWGs include:

  • Resist Sub-TWG: During the August meeting, members presented findings from resist exposure tests conducted in June at the Center for X-Ray Optics (CXRO). Blue – X TWG is currently developing a Statement of Work with CXRO to secure beamline access in Q4 2025 and again in 2026, supporting advanced resist exposure and metrology studies focused on 6.7 nm and the water-window region (2.2–4.4 nm). Further experiments are being considered at international beamline facilities, with more details to be announced soon.
  • ML Optics Sub-TWG: Ongoing discussions include plans for fabricating multi-layer optics tailored to the water-window region and collaborating with CXRO for precise measurement activities. Additional initiatives involve aligning ML optics with plasma source technology, conducting modeling enhancements via a round-robin project, and exploring innovative methods to optimize multilayer reflectivity.
  • Plasma Source and Atomic Data / Modeling Sub-Sub TWGs: This subgroup is dedicated to identifying plasma sources that support advanced lithography in the water-window region and are compatible with ML optics offering high peak reflectivity. The upcoming meeting on September 11th will focus on evaluating various plasma source options and formulating strategies for continued research.

The Blue – X TWG remains committed to advancing the field and will continue to share with its members the significant achievements as exploration in leading – edge lithography at sub -13.5 nm progresses. 

Blue – X Annual In-Person Meeting and Resist Sub-TWG Conducts Resist Exposure Studies at < 13.5 nm

The Blue-X TWG held its annual in-person meeting on June 23, 2025, at MIT Lincoln Laboratory, gathering over 80 experts from around the globe. The Blue – X TWG now comprises 70 member organizations, collectively assigning 200 representatives to the group. The newest members include Asahi Glass, Osaka University, and Trumpf.

The Blue – X TWG has officially commenced experimental investigations into advanced lithography processes at wavelengths below 13.5 nm. On June 13, 2025, the Resist sub-TWG conducted resist exposure tests at 6.7 nm, evaluating eight different resist chemistries provided by four groups encompassing both academic institutions and commercial suppliers. These experiments were carried out at the CXRO beamline at LBL. Initial results were presented during the in-person meeting on June 23.
Final Agenda – Blue-X Annual In–person Meeting (Please see the agenda for Day 1, June 23, 2025)

Group Photograph – 2025 Annual In-person Meeting 

To join, the Blue – X TWG, please contact us at info@euvlitho.com. Additional information about the TWG is available at www.euvlitho.com/Blue-X.

Nikon Research Corporation of America (NRCA) Joins Blue – X Consortium to Explore Leading-Edge Lithography at < 13. 5 nm. 

The Blue – X consortium has recently welcomed six new members, including Nikon Research Corporation of America (NRCA), expanding its collaborative network to explore advanced optical projection lithography at wavelengths below 13.5 nm. EUV Litho, Inc. organizes this consortium as a Technical Working Group (TWG), which now comprises over 65 members who collectively have assigned more than 170 professionals to various sub-TWGs.

Among the distinguished members are major chip manufacturers such as IBM and Intel, along with a mix of large and small original equipment manufacturers (OEMs), National Labs, and independent experts from around the globe. This diverse group aims to push the boundaries of advanced lithography beyond 13.5 nm by harnessing collective expertise and fostering innovation across several specialized sub-TWGs. These sub-groups tackle critical areas, including Imaging and Optical Design, Optics, Mask, Metrology, Resist and Patterning and various Photon Source technologies.

The consortium also is engaging in initiatives such as Resist Evaluations at beamlines, ML optics development, optical design evaluations and Source Evaluations through programs like Flying Circus. These efforts underscore the Blue – X consortium’s dedication to advancing research and technology in the field. Detailed program information will be released soon.

The annual in-person meeting of the Blue – X TWG is scheduled for June 23rd at MIT LL. This event is exclusive to Blue-X TWG members, with a registration deadline of May 23rd. This meeting presents a unique opportunity to engage with leading experts and explore the next wave of technological innovations beyond EUV. Interested parties are encouraged to contact info@euvlitho.com for program updates, white papers, and membership information. The detailed agenda for the meeting, along with information for the 2025 EUVL and Source Workshop, has been announced on www.euvlitho.com.

Blue – X Sub TWGs Launched

We successfully organized an all sub -TWGs meeting on April 15, 2025. Previously we had a successful launch of nine Sub Technical Working Groups (sub TWGs) within the Blue -X Consortium from February 10-12, 2025! Led by industry experts, these groups will delve into various areas including Imaging, Resist, Mask, ML Optics, Sources and more, aiming to pave the way for advanced lithography below 13.5 nm. With the Consortium now boasting 57 members and approximately 150 assignees, including recent additions like Corning, PSI, Merck and TEL, the collaborative efforts are set to push the boundaries of technology. The meeting agenda, exclusively for members, can be accessed through the provided link. Let’s embark on this journey together as we delve into the next phase of technology advancement, driving the extension of Moore’s Law!

Previously: Blue – X Consortium Successfully Launched!

EUV Litho Inc. is pleased to announce Phase I of Blue-X, a consortium to investigate the potential of optical projection lithography in the wavelength region of 2–7 nm. The consortium was formally revealed during the 2024 Source Workshop in Amsterdam this October.

During Phase I, Blue – X is being organized as a technical working group (TWG), with sub- groups being formed in the areas of Source, Optics, Mask, Imaging and Resist. We currently have 37 organizations as members, including chip makers, original equipment manufacturers (OEMs), a university and national labs. These members have assigned approximately 110 professionals to participate in this TWG. We expect additional organizations to join and the number of TWG members to increase!

The first meeting of Blue – X TWG was held on Dec. 10 via Zoom. Meeting recording and presentations are available to Blue – X TWG members. Future periodic meetings will also be offered on Zoom, with an in-person gathering in June during the 2025 EUVL and Source Workshop at MIT LL.

If your organization is interested in finding out more about Blue – X, please contact us at info@euvlitho.com to request a copy of  the White Paper. The process of joining the TWG is very simple and we will be happy to help you with it. The organizations, joining the TWG after December 10, 2024, will still have access to meeting proceedings and technical information produced by the TWG.