The United States is making efforts in EUV lithography.
In the field of advanced chip manufacturing, EUV lithography machines are an important component that cannot be overlooked. When it comes to EUV lithography, ASML is the first company that comes to mind. Indeed, as a leading lithography machine manufacturer in the market, ASML's strength in lithography machines cannot be ignored. Especially in the currently highly - concerned EUV lithography machines, ASML has become the world's sole supplier.
However, as the birthplace of the global semiconductor industry, the United States' strength in EUV lithography also cannot be underestimated. Although it doesn't have EUV lithography machines, the key light source component is developed by Cymer, a US company acquired by ASML.
In recent years, as the United States aims to achieve greater success in chip manufacturing, it has made more investments in EUV lithography. For example, Intel, a US chip giant, has made significant investments in this area. In addition, the US has also made more arrangements in EUV research and other lithography - related fields.
Investing Heavily in EUV Lithography
The United States recently announced the grand opening of its CHIPS for America Extreme Ultraviolet (EUV) Accelerator.
In December 2023, New York State in the US announced a new $10 billion partnership with semiconductor industry leaders such as IBM, Micron, Applied Materials, and Tokyo Electron to establish a next - generation semiconductor R & D center at the Albany Nanotech Complex of NY CREATES.
It is reported that this public - private partnership will fund the construction of a cutting - edge High NA Extreme Ultraviolet Lithography Center - the first and only public High NA EUV center in North America. This center will support the R & D of the world's most complex and powerful semiconductors. In addition to the transformative investment in the Capital Region of New York State, this cooperation will also make New York State the location of the most advanced public semiconductor R & D infrastructure in the United States, supporting the long - term growth of the state's technology economy.
To support this project, New York State has invested $1 billion to expand the Albany Nanotech Center. It established a High NA EUV center by purchasing ASML's EXE:5200 high - numerical - aperture EUV scanner and built the NanoFab Reflection. This factory is a brand - new and highly advanced building with over 50,000 square feet of clean - room space, which will promote the development of future partners and support new projects such as the National Semiconductor Technology Center, the National Advanced Packaging Manufacturing Program, and the Department of Defense's Microelectronics Commons Program.
The United States stated that the EUV Accelerator will focus on developing the most advanced high - numerical - aperture EUV technology and its related R & D. They pointed out that EUV lithography technology has become the key technology for mass - producing transistors above 7 nanometers. Although in the 1.6 - nanometer and 1.4 - nanometer processes, sub - 2 - nanometer processes still use high - numerical - aperture EUV. ASML said that the center will support a wider range of companies in developing process steps using EUV and high - numerical - aperture EUV.
Overall, the main functions of this EUV Accelerator include:
- Using cutting - edge EUV lithography tools and next - generation R & D capabilities, including high - numerical - aperture (NA) EUV systems. Currently, standard NA EUV is provided, and High NA EUV is expected to be available in 2026.
- Providing cooperation space and resources for industry, academia, and government partners to promote technological innovation.
- A dedicated on - site Natcast office and staff to support Natcast and NSTC member researchers. Supporting programs to provide, train, and develop the talent pool.
- Promoting the extensive participation of NSTC members by creating an open and collaborative R & D environment within the EUV Accelerator and all NSTC facilities.
The US government said that obtaining R & D in EUV lithography technology is crucial for expanding the United States' technological leadership, reducing the time and cost of prototyping, and establishing and maintaining a semiconductor labor ecosystem.
Deirdre Hanford, CEO of Natcast, said: "The grand opening of the EUV Accelerator is a milestone for Natcast, NSTC, and the entire US semiconductor ecosystem. This advanced facility demonstrates our commitment to developing and advancing next - generation semiconductor technologies in the United States. EUV lithography technology has become the key technology for mass - producing transistors above 7 nanometers. Although in the 1.6 - nanometer and 1.4 - nanometer processes, sub - 2 - nanometer processes still use high - numerical - aperture EUV. The center will support a wider range of companies in developing process steps using EUV and high - numerical - aperture EUV."
Exploring Alternatives to EUV
In addition to making efforts in the current EUV field, from reports in the past few years, we can see that US companies are also working on alternative technologies for EUV lithography.
In April this year, US startup xLight announced that it hopes to use a particle accelerator to generate light for lithography machines and claims that it can produce such a light source by 2028 while maintaining compatibility with existing tools. xLight stated on its official website that the company's mission is to commercialize particle - accelerator - driven free - electron lasers (FEL: Free Electron Lasers) to meet the key economic and national security applications in the United States. xLight also pointed out that the company is building the world's most powerful laser to revolutionize semiconductor lithography, metrology technology, and other key economic and national security applications.
It is reported that laser - produced plasma is currently the only method for generating EUV light used in cutting - edge semiconductor manufacturing. However, it consumes extremely high power (about 1.5 MW of electricity can only produce 500 W of light) and cannot fully support ASML's existing and future versions of scanners, as these scanners require a light - source power of up to 2 kW.
"We have developed a brand - new extreme ultraviolet (EUV) free - electron laser (FEL) light source for the semiconductor market to replace the current laser - produced plasma (LPP) light source, which is approaching its physical limit. Our FEL system will significantly enhance ASML's technology roadmap, reduce capital and operating costs, improve the production capacity of semiconductor fabs, and help the United States regain its leading position in the field of advanced semiconductors," xLight emphasized.
In May, another US company named Inversion Semiconductor emerged. It is reported that Inversion Semiconductor aims to use a "desktop" particle accelerator to generate the required high - power light. This accelerator can accelerate electrons to extremely high energies within a centimeter - scale range, rather than requiring a kilometer - scale like the large accelerators at CERN and SLAC. They hope to achieve this goal by using plasma waves (Wakefield) driven by high - power lasers. Specifically, it is a technology called Laser Wakefield Acceleration (LWFA).
In principle, LWFA uses the interaction between a strong laser pulse and plasma to accelerate electrons to extremely high energies within a very short distance. This process is similar to a surfer riding a wake behind a boat: electrons "surf" on the plasma wave and gain energy as they travel.
By leveraging this phenomenon, a compact and high - power light source can be generated. Inversion expects that LWFA can shrink the traditional particle accelerator used to generate high - energy light by 1000 times to a desktop size, that is, its size will be reduced from several kilometers to about one meter; with the same numerical aperture (NA), the transistor density can be increased by 100%; based on this technology, the critical - dimension uniformity can be improved by 25%, significantly improving the manufacturing of high - aspect - ratio features of new transistor architectures and computing paradigms (including quantum and reversible).
The company said that its goal is to generate 1 kilowatt of soft X - rays (from 20 nanometers to 6 nanometers). If successful, this milestone will lay the foundation for the construction of a user facility, and booking beam time will be as simple as booking a SpaceX launch - just use a credit card.
At the same time, the company will develop a new mirror system for reflecting and focusing the generated X - rays. This will enable us to demonstrate silicon patterning using the initial LITH - 0 system driven by STARLIGHT.
According to Inversion's plan, the company will use its advanced light source to project patterns, just like traditional EUVL, but this light source can be tuned to a wavelength of 13.5 nanometers or lower, and the target wavelength for the next generation is 6.7 nanometers. In addition, the company claims that it can double the transistor density with the same numerical aperture while achieving three times the throughput of existing machines. The brightness of this light source may also be sufficient to illuminate multiple wafer stages, so one light source paired with four or eight lithography machines will further improve manufacturing efficiency.
Japan and Europe are also Exploring New Opportunities
Actually, in addition to the United States, Japan and Europe are also exploring new opportunities in EUV lithography.
For example, Norwegian startup Lace Lithography AS said that it is developing a lithography technology that uses atoms emitted towards the surface to define features, and its resolution exceeds the limit of extreme ultraviolet lithography technology. It is understood that the so - called BEUV by Lace Litho can theoretically achieve finer features, support the continuous miniaturization of transistors, and extend Moore's Law.
As is well - known, traditional EUV systems use light with a wavelength of 13.5 nm to form patterns on the wafer through a series of mirrors and masks. Atomic lithography technology can achieve direct mask - less patterning, and its resolution is even smaller than that achievable by EUV systems limited by wavelength.
The company claims on its website: "By using atoms instead of light, we offer chip manufacturers capabilities that are 15 years ahead of current technology, with lower costs and lower energy consumption."
It is understood that this project comes from a project named FabouLACE funded by the EU. Specifically, it uses metastable atoms and masks based on dispersion forces to achieve a 2 - nanometer process. The European Commission said that Lace lithography technology has been authorized to bring this technology to the market by 2031. Meanwhile, the performance of this technology will be monitored and verified by the IMEC research institution. NanoLACE is an early European research project that ended on December 31, 2024. This project was launched in 2019 and has received 3.36 million euros in funding, with a budget of 3.65 million euros.
A group of researchers from the High - Energy Accelerator Research Organization (KEK) in Tsukuba, Japan, also believe that if the energy of a particle accelerator is utilized, EUV lithography technology could be cheaper, faster, and more efficient.
Stephen Benson, a retired senior researcher at the Thomas Jefferson National Accelerator Facility in Virginia, USA, once estimated that the electro - optical conversion efficiency of the entire EUV - LPP system may be less than 0.1%. He said that a free - electron laser like the one KEK is developing could be 10 to 100 times more efficient.
It is reported that the system KEK is developing generates light by accelerating electrons to relativistic speeds and then deflecting their motion in a specific way. As they said, this process starts when an electron gun injects an electron beam into a several - meter - long cryogenically - cooled tube. Inside this tube, a superconductor emits radio - frequency (RF) signals to drive the electrons to move faster and faster. Then the electrons rotate 180 degrees and enter a structure called an undulator, which is a series of magnets with opposite directions. (The KEK system currently has two.) The undulator forces the high - speed electrons to move along a sinusoidal path, and this motion causes the electrons to emit light.
Conclusion
In fact, the development of modern lithography machines to the present stage is the result of many technological explorations and attempts. In other words, many current solutions may have been tried in the past but failed, perhaps due to the limited understanding at that time.
From ASML's sharing, we also understand that it is not impossible to continue advancing EUV lithography. For example, in terms of numerical aperture, the company is on the path of evolving from High NA to Hyper NA. We cannot predict what new methods will emerge in the future.
However, it is certain that the continuous improvement of chip performance is a foregone conclusion. The question lies in whether it depends on EUV lithography or other technologies such as packaging.
This article is from the WeChat official account "Semiconductor Industry Observation" (ID: icbank), author: Editorial Department, published by 36Kr with authorization.