Interview: What’s next in lithography?
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Andreas Thoss
In September 2017 AOT Editor in Chief Michael Pfeffer visited Dr. Michael Liehr in Rochester, N.Y., to talk with him about recent progress in EUV lithography. Dr. Liehr is not only CEO of the new American Institute for Manufacturing for Integrated Photonics (AIM), but also Executive Vice President for Innovation and Technology and Vice President for Research at SUNY Polytechnic Institute (SUNY Poly) in Albany.
AOT: What do you see as the key achievements solved for EUV lithography already?
Liehr: It took time, but now we can say that the migration from UV refractive systems to reflective soft X-ray technology is on its way to mass production. This is everything but simple. The source power had to be brought up, and resist photo speed and outgassing problems had to be overcome.
Initial challenges with mask shadowing effects and defect levels have also been sufficiently addressed. And while each of those technical developments has progressed, the technology uptime has reached the level of 80 percent; with ASML working aggressively to a next goal of 90 percent.
The ASML TWINSCAN NXE:3300B EUV lithography tool at the SUNY Polytechnic Institute cleanroom in Albany, NY.
AOT: What is left to be done, and how far are we from high volume manufacturing (HVM)?
Liehr: Source power and reliability remain key issues. ASML has demonstrated 210 W EUV source power in their labs, but there is still some way to go until 250 W is available in mass production. This power level enables scanner throughput of 125 wafers per hour. The overall machine speed depends mainly – but not only – on the EUV source.
Other challenges continue for EUV resist performance. Although EUV lithography processes in vacuum, it is still approaching its natural limitation in physics. Meeting the requirements of resolution, line-edge-roughness, and sensitivity is still something to work on.
The same holds for the continued decrease in mask defects, including establishing a pellicle option.
The main question is how long it will take until the current systems are ready for high-volume manufacturing. I can’t tell you, but I expect more information from ASML in their November conference.
AOT: What comes next in lithography?
Liehr: That’s hard to say. Next advances will definitely include an increase in numerical aperture for EUV. Maybe multi-pass EUV? Advanced e-beam on-wafer lithography? We already see interesting multi-column e-beam approaches for mask processing.
Imprint technologies have made remarkable progress recently, but can they overcome the challenges of material science when approaching molecular-scale resolution and alignment?
About AIM Photonics
AIM Photonics is one of a number of Manufacturing Innovation Institutes, an industry-driven public-private partnership that focuses the nation’s premiere capabilities and expertise to capture critical global manufacturing leadership in a technology that is both essential to national security and positioned to provide a compelling return-on-investment to the US economy. For more information about AIM Photonics, visit http://www.aimphotonics.com/
About SUNY Polytechnic Institute (SUNY Poly)
SUNY Poly is New York’s globally recognized, high-tech educational ecosystem. SUNY Poly offers undergraduate and graduate degrees in the emerging disciplines of nanoscience and nanoengineering, as well as cutting-edge nanobioscience and nanoeconomics programs at its Albany campus, and undergraduate and graduate degrees in technology, including engineering, cybersecurity, computer science and the engineering technologies; professional studies, including business, communication and nursing; and arts and sciences, including natural sciences, mathematics, humanities and social sciences at its Utica/Rome campus; SUNY Poly boasts billions of dollars in high-tech investments and hundreds of corporate partners since its inception. For information visit www.sunypoly.edu.
Dr. Michael Liehr, Vice President for Research and CEO, AIM Photonics, holds the world’s first 7 nm node test chip; produced using several EUV-printed layers in the SUNY Polytechnic Institute cleanroom in Albany, NY.
Andreas Thoss
Publisher
Advanced Optical Technologies
©2017 THOSS Media & De Gruyter, Berlin/Boston
Articles in the same Issue
- Cover and Frontmatter
- Views
- Interview: What’s next in lithography?
- Community
- News from the European Optical Society EOS
- News
- Topical issue: Ptychography
- Editorial
- Special issue on ptychography
- Tutorial
- An introduction to the theory of ptychographic phase retrieval methods
- Review Articles
- Coherent diffractive imaging methods for semiconductor manufacturing
- Fourier ptychography for high space-bandwidth product microscopy
- Research Articles
- Ptychographic imaging with partially coherent plasma EUV sources
- Effects of illumination on image reconstruction via Fourier ptychography
- Data compression strategies for ptychographic diffraction imaging
- Measurement of large optical elements used for inertial confinement fusion with ptychography
- Research Article
- Design of pre-optics for laser guide star wavefront sensor for the ELT
Articles in the same Issue
- Cover and Frontmatter
- Views
- Interview: What’s next in lithography?
- Community
- News from the European Optical Society EOS
- News
- Topical issue: Ptychography
- Editorial
- Special issue on ptychography
- Tutorial
- An introduction to the theory of ptychographic phase retrieval methods
- Review Articles
- Coherent diffractive imaging methods for semiconductor manufacturing
- Fourier ptychography for high space-bandwidth product microscopy
- Research Articles
- Ptychographic imaging with partially coherent plasma EUV sources
- Effects of illumination on image reconstruction via Fourier ptychography
- Data compression strategies for ptychographic diffraction imaging
- Measurement of large optical elements used for inertial confinement fusion with ptychography
- Research Article
- Design of pre-optics for laser guide star wavefront sensor for the ELT
