Russia may be attempting one of the most ambitious semiconductor technology advances in modern history. Scientists from the Keldysh Research Center, TRINITI, and the Institute for Spectroscopy of the Russian Academy of Sciences have proposed a new technique for producing high-energy X-ray radiation. This approach has the potential to facilitate the operation of domestic lithography systems at the 1–3 nanometer level.
If feasible, this concept could allow Russia to bypass multiple generations of conventional semiconductor manufacturing and reduce reliance on foreign lithography systems dominated by ASML.
The proposal centers on a radiation source fundamentally distinct from lithography devices. Russian researchers are currently investigating a 6.7-nanometer X-ray wavelength as an alternative to the 13.5-nanometer extreme ultraviolet wavelength used in conventional state-of-the-art EUV systems. In theory, this transition could enable the fabrication of transistor structures significantly smaller than those currently feasible using conventional EUV lithography.
Why the Semiconductor Industry Is Approaching a Physical Wall
Lithography systems are essential for producing modern chips, as they project microscopic patterns onto silicon substrates. The transistor features that can be printed are proportional to the wavelength of light used in the process.
Before transitioning to EUV systems operating at 13.5 nm, the semiconductor industry advanced through deep ultraviolet lithography for years. This machinery is among the most complex industrial systems ever built. Tens of thousands of components, plasma light sources, multilayer mirrors, ultra-precise positioning systems, and highly specialized vacuum chambers are all present in a single modern EUV lithography platform.
Nevertheless, the industry is rapidly approaching its physical limits. The difficulty and cost of achieving reliable patterning with 13.5 nm radiation increase as transistor structures continue to shrink. Extreme optical precision, multiple exposure passes, and increasing power requirements have all become significant constraints.
Russian researchers currently maintain that the next significant advancement may necessitate completely discontinuing conventional EUV scaling and transitioning to the soft X-ray range, specifically around 6.7 nm. This radiation has the potential to reduce some of the scaling constraints associated with conventional photomasks and support transistor densities that exceed current EUV capabilities.
The Core Idea: Creating an Advanced X-Ray Plasma Source
The Russian proposal focuses primarily on producing high-efficiency plasma capable of emitting radiation at the desired wavelength.
The researchers found that the conversion efficacy of rare-earth refractory metals, such as gadolinium and terbium, from laser energy to X-ray emission is particularly high. These materials have the potential to generate the intensive radiation required for next-generation lithography systems, as indicated by the published research.
Radiation generation is not the only obstacle. The genuine engineering challenge is performing this process continuously without damaging the internal components and optics of the lithography machine.
Currently, tin droplets are often used as targets in EUV systems. Plasma is generated by the impact of high-power laser pulses on microscopic droplets of molten tin, resulting in EUV radiation emission. However, this method creates a significant contamination issue. The intended material does not undergo complete vaporization. Mirrors are eventually coated, pumps are damaged, and the system’s lifespan is reduced due to the spread of small fragments and material debris throughout the vacuum chamber.
This contamination issue has emerged as one of the main engineering challenges in the global development of advanced lithography.
Russia’s Alternative to Tin Droplet Technology
Russian technologists are advocating for a gas-based target system as an alternative to solid or liquid targets.
Their concept requires directly introducing pre-heated gadolinium vapor into the irradiation zone, resulting in the formation of a controlled gaseous cloud with the necessary density. The amount of solid debris may possibly be reduced due to the fact that the target material is already in gaseous form.
This represents a major departure from conventional EUV source architecture.
The method has the potential to substantially enhance the cleanliness of the process and minimize the contamination of costly multilayer mirrors within the lithography chamber. This finding is significant because mirror degradation is one of the most significant operational constraints in contemporary EUV systems.
Additionally, the concept has the potential to simplify thermal management and refuse handling compared to current droplet synchronization systems, which necessitate intricate cooling infrastructure and extremely precise timing.
The Challenge of Extreme Temperatures
Although the gas-target concept has the potential to reduce contamination, it also introduces an additional big engineering challenge.
Gadolinium undergoes fusion at temperatures exceeding 1500 degrees Celsius. Therefore, to produce an adequate vapor pressure for the proposed X-ray source, the material must be raised to a temperature of approximately 3000 degrees Celsius or higher.
The majority of conventional metals experience abrupt failure at temperatures of this magnitude.
Consequently, the researchers suggested using crucibles fabricated from exotic tungsten-rhenium alloys capable of withstanding temperatures approaching 3600 Kelvin. These thermal conditions are exceedingly difficult for industries such as aerospace and nuclear.
Extremely sophisticated thermal control systems and materials engineering would be necessary to ensure stable operation within a high-temperature lithography environment while preserving precision plasma characteristics.
However, the Russian team believes the concept is feasible given the current state of high-temperature technologies.
Electron Beam Heating Instead of Conventional Lasers
The proposal’s use of an electron beam generator for vapor production, as opposed to conventional laser heating, is one of its most intriguing features.
The researchers have identified numerous significant benefits of electron beam heating. However, electron beam generators can function within buffer gases, including helium or argon, in contrast to numerous conventional laser systems. This capability is regarded as essential for consistent lithography operation.
The proposed vapor generation process would require an estimated 1.2 kilowatts of thermal power, according to the study. Researchers also note that using reflective heat barriers, such as silver-coated surfaces, has the potential to greatly reduce thermal losses.
In practical terms, this implies that the target generation system’s overall power requirements could remain relatively compact compared to the extensive infrastructure associated with certain extant EUV systems.
The Significance of the 6.7 nm Transition
The transition from 13.5 nm EUV to 6.7 nm soft X-ray radiation would necessitate developing new optical systems and a new plasma source.
X-rays can pass through the majority of materials, rendering conventional lenses ineffective. Instead, lithography systems depend on highly advanced multilayer mirrors that are specifically engineered to reflect extremely narrow wavelength bands.
Recent developments in multilayer mirror technology, which are based on lanthanum and boron structures, are indicated by the Russian research. The proposed wavelength is believed to have the potential to achieve theoretical reflectivity levels of approximately 80 percent.
If such mirror performance can be achieved in real industrial conditions, it would provide a significant enabling technology for future X-ray lithography systems.
This is particularly significant because optical efficiency is one of the defining limitations of advanced lithography. Even slight reflectivity losses compound rapidly across multiple mirror stages.
A Potential Leap Beyond Current EUV Systems
The Russian proposal is particularly noteworthy because it does not just replicate existing EUV technology. Rather, the concept is designed to advance directly toward a shorter-wavelength lithography generation that has the potential to surpass current commercial systems.
That is an uncommonly ambitious approach.
The primary objective for most countries striving for semiconductor independence is mastering existing manufacturing methods and mature process nodes. Instead, Russia’s proposed strategy implies an ongoing effort to completely circumvent certain segments of the current technological hierarchy.
The feasibility of such a leap remains uncertain. Semiconductor lithography is one of the most challenging industrial technologies ever developed, necessitating proficiency in plasma physics, optics, materials science, vacuum engineering, ultra-precision mechanics, and sophisticated software control systems.
The capabilities of ASML and its supply chain ecosystem have been difficult for even the most established industrial entities to replicate.
However, the Russian initiative seems focused on a highly specific niche: generating compact, high-temperature gas targets for short-wavelength X-ray lithography.
No direct foreign equivalent of such a compact gadolinium gas-target system has been publicly documented in scientific literature, according to the available publication.
The Next Step: Construction of a Laboratory Prototype
The researchers recognize that there is still a significant amount of engineering work to be done.
According to reports, the next stage will consist of developing a laboratory prototype using low-cost molybdenum components, followed by transitioning to costly tungsten-rhenium alloys for full-scale testing.
This phased development approach implies that the project is still in the early experimental phase, rather than being close to industrial deployment.
A laboratory plasma source demonstration differs vastly from developing commercially viable lithography equipment capable of high-volume semiconductor production.
Modern lithography platforms necessitate exceptional reliability, uptime, precision alignment, contamination control, and software integration. The challenge is not limited to developing a radiation source.
Strategic Importance for Russia
The research underscores Russia’s increasing emphasis on technological sovereignty in semiconductor manufacturing, despite the technical challenges.
Russian access to sophisticated semiconductor equipment has been significantly restricted by Western export restrictions. Consequently, domestic research organizations are increasingly experimenting with unconventional methods to decrease their reliance on foreign suppliers.
The Keldysh Research Center and TRINITI’s participation is especially noteworthy due to their extensive knowledge of plasma physics, high-energy systems, and extreme-temperature engineering, which was acquired through aerospace and nuclear research programs.
This background may offer valuable capabilities for experimental lithography technologies that involve plasma generation and advanced thermal systems.
Could Russia Really Build a 1–3 nm Lithography System?
Currently, the initiative is characterized by a high degree of theoretical and experimental content. There is no indication that Russia is on the brink of establishing a production-ready lithography platform that is capable of directly competing with contemporary commercial EUV systems.
Nevertheless, the significance of the research is in its direction, rather than its immediate commercialization.
The proposal illustrates that Russian scientists are pursuing post-EUV lithography concepts rather than merely replicating older technologies. Future semiconductor manufacturing research could be influenced by even a limited success in high-efficiency X-ray plasma generation.
It is possible that the project could change the assumptions regarding the future global semiconductor landscape if it eventually transitions from laboratory experiments to scalable industrial systems.
At present, the research offers a fascinating look into Russia’s aspirations for one of the world’s most critical technologies: the capacity to produce the next iteration of sophisticated chips domestically.