💡 MoS2—the "ultimate thin" semiconductor material poised to succeed silicon. Creating uniform monolayer films across entire wafers has long been considered impossible. Now, researchers from Japan's NIMS and the University of Tokyo have achieved the world's first wafer-scale deposition of films just three atoms thick, marking a revolutionary breakthrough in next-generation semiconductor technology.
Silicon's Limits and the Quest for Next-Generation Semiconductors
Semiconductor miniaturization has followed Moore's Law for decades, but conventional silicon-based technology is approaching fundamental physical limits. At today's cutting-edge 2-3nm process nodes, transistor channels are only a few nanometers thick, making quantum tunneling effects and leakage currents increasingly problematic.
Major semiconductor companies like TSMC, Intel, and Samsung are accelerating research into alternative materials for the post-silicon era of the 2030s and beyond. The leading candidates are two-dimensional materials known as transition metal dichalcogenides (TMDs).
What Is Molybdenum Disulfide (MoS2)?
MoS2 (molybdenum disulfide) is a representative TMD material. A monolayer of MoS2 consists of a layer of molybdenum (Mo) atoms sandwiched between two layers of sulfur (S) atoms—a sandwich structure with an ultimate thickness of only about 0.65nm, just three atoms thick.
Traditionally, MoS2 has been used industrially as a lubricant. Its layered structure, held together by weak van der Waals forces between layers, allows the layers to slide easily, resulting in a low friction coefficient. However, researchers recently discovered that when reduced to a monolayer, this material becomes a direct bandgap semiconductor with excellent electrical properties.
Monolayer MoS2 has a bandgap of approximately 1.8eV and can achieve high on/off ratios and electron mobility—ideal characteristics for next-generation ultra-low-power devices.
A Technical Breakthrough Through Industry-Academia Collaboration
On January 21, 2026, a research group led by Yoshiki Sakuma, NIMS Distinguished Researcher at the National Institute for Materials Science (NIMS), and Professor Kosuke Nagashio from the University of Tokyo's Graduate School of Engineering published groundbreaking results in Nature Communications. The collaborative research included Nagoya University, the University of Tsukuba, and semiconductor equipment giant Tokyo Electron Technology Solutions.
The research team discovered two critical mechanisms when growing monolayer MoS2 using metalorganic chemical vapor deposition (MOCVD):
Self-alignment mechanism: MoS2 crystal grains growing on sapphire substrates spontaneously align their crystal orientations as they merge, ultimately forming a single crystal.
Self-limiting mechanism: Using uniquely selected precursors (source gases), the deposition reaction automatically stops at monolayer thickness.
Through the synergistic effect of these two mechanisms, the team achieved uniform and reproducible epitaxial growth of monolayer MoS2 across entire 2-inch sapphire wafers.
Quality Verification: Electron Mobility Evaluation
The researchers evaluated film quality through temperature-dependent electron mobility measurements. In high-quality semiconductors, lower temperatures reduce lattice vibrations (phonons), suppressing electron scattering and increasing mobility. In contrast, materials with many defects show defect-dominated scattering, limiting mobility improvements even at low temperatures.
Measurements confirmed that MoS2 films produced by this method showed significantly improved mobility at lower temperatures—demonstrating extremely low defect density and confirming the formation of high-quality single-crystal films.
The Technology Industry Has Been Waiting For
What makes this achievement groundbreaking is its "wafer-scale" nature. While laboratory methods like mechanical exfoliation (the "scotch tape method") can produce high-quality monolayer MoS2, they only yield micrometer-sized flakes—completely unsuitable for large-scale integrated circuit manufacturing.
The semiconductor industry has established processes for forming uniform thin films on large-diameter wafers (200-300mm) and batch-processing thousands to tens of thousands of chips simultaneously. While this research uses 2-inch (approximately 50mm) wafers, it demonstrates uniform film formation across entire wafers using MOCVD—a method compatible with industrial manufacturing processes.
Tokyo Electron's participation in this collaborative research underscores the high expectations for industrializing this technology.
The Path to Sub-1nm Node Transistors
Current cutting-edge semiconductors are at the 3nm node, but the industry is pushing for further miniaturization. TSMC plans to begin mass production of its 1.6nm node (A16) by late 2026, with "sub-1nm nodes" on the horizon beyond that.
At sub-1nm nodes, transistor channel thickness reaches extreme limits where conventional silicon cannot suppress electron tunneling. Monolayer MoS2, functioning as a semiconductor at just 0.65nm thick, emerges as a leading candidate material for realizing sub-1nm node logic transistors.
Remaining Challenges and Future Outlook
Several challenges remain before this technology reaches commercialization.
First, wafer size scaling—expansion to 300mm wafers standard in industry is necessary. Additionally, interface control between MoS2 and metal electrodes, realization of p-type semiconductors (not just n-type), and integration with existing CMOS manufacturing lines are critical issues.
However, the discovery of the "self-alignment" and "self-limiting" mechanisms provides essential foundational technology for addressing these challenges. The research group states that this achievement will significantly contribute to future large-scale integrated circuits, low-power electronics, and optoelectronic device applications.
Japan's Materials Science Leading the World
This research showcases Japan's strengths in materials science. NIMS is one of the world's premier materials research institutions, and collaboration between universities like the University of Tokyo and Tokyo Electron, a leading equipment manufacturer, made this achievement possible.
While Japan's presence in the semiconductor industry has declined in recent years, it maintains world-class technological capabilities in materials and manufacturing equipment—the "unsung heroes" of the industry. How Japan's fundamental research will shape the future of next-generation semiconductors remains a story worth watching.
In Japan, research into next-generation semiconductor materials that surpass silicon's limits continues to advance steadily. This technology could determine the future of the semiconductor industry. Is similar research being conducted in your country? What are your thoughts on next-generation semiconductor materials and the efforts being made where you live? We'd love to hear your perspectives.
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Reactions in Japan
Amazing joint research from NIMS and UTokyo! Being able to create MoS2 monolayer films across entire wafers is revolutionary for the semiconductor industry! Japan's materials science is still world-class.
Self-alignment and self-limiting—what clever mechanisms. It aligns itself and stops on its own. It's almost like the material is 'thinking for itself.' Fascinating.
Tokyo Electron's involvement is key. You can tell they're aiming for practical applications through industry-academia collaboration. I see hope for Japan's semiconductor revival.
Isn't a 2-inch wafer pretty small? Industrial standard is 300mm. Feels like commercialization is still far away...
Sub-1nm transistors—we're talking atomic scale now. Materials that surpass silicon's limits have finally arrived. This is exciting!
MoS2 was used as a lubricant, right? The fact that it could become a next-gen semiconductor shows how fascinating materials science is.
Published in Nature Communications! Passing peer review means it's solid research. Congratulations!
I wonder how many years until mass production is possible. There's always a big gap between research and commercialization.
Japan's been losing to TSMC and Korean companies in miniaturization, but this could be Japan's chance to fight back with materials. Go Japan!
Evaluating quality through temperature-dependent electron mobility is scientifically sound and trustworthy. Low defect density is a major advantage.
Will this make smartphone batteries last longer? It mentions low power consumption, so I'm hopeful.
MOCVD is already used in existing production lines, so the barrier to industrialization might be lower. That's the key point.
But there are still mountains of challenges like realizing p-type semiconductors and electrode interface control. Let's not get too excited.
I can't even imagine a film just 3 atoms thick... 0.65nm is invisible to the naked eye.
Supported by JST CREST. Good to see national research investment actually producing results.
As a semiconductor engineer, this is genuinely impressive. No one has achieved uniform monolayer films across entire wafers before.
Chinese and Korean research groups are working in the same field, so competition must be fierce. Let's see if Japan can stay ahead.
It mentions optoelectronic device applications too. Could be used for displays and sensors? Seems to have wide applications.
Semiconductor engineer from Taiwan here. TSMC is also researching 2D materials, but this NIMS achievement is impressive. Uniformity across entire wafers was a major challenge. Japan's materials science is truly strong.
Graduate student in the US researching the same field. The discovery of the self-alignment mechanism is groundbreaking! Our lab uses MOCVD too, but we haven't achieved results like this. Can't wait to read the full paper.
Working at a German research institute. Similar research is being done in Europe, but Japan is clearly leading in this field. Their industry-academia collaboration model is also worth learning from.
Samsung in Korea is also investing in 2D materials, but this kind of fundamental research achievement is admirable. However, the road to mass production is still long. The competition continues.
MoS2 research is thriving in China too, at universities like Tsinghua. I acknowledge Japan's research team's achievements, but China isn't falling behind. International competition in this field will intensify.
Researching nanomaterials at IIT in India. Japan's precision in materials control is truly remarkable. India is trying to develop its semiconductor industry, but building this kind of fundamental research capability will take time.
Working at a UK semiconductor startup. 2D materials definitely have potential, but I think it'll take 10+ years to replace silicon. That said, this research is an important step forward.
Physics professor from Spain. The self-limiting mechanism discovery is particularly interesting. This could potentially be applied to other 2D materials. Looking forward to reading the details in Nature Communications.
Semiconductor analyst in Silicon Valley. Japan's NIMS is world-class in materials research. However, there are still many hurdles before this tech can be used in Intel or TSMC fabs.
Researcher from Poland. In Europe, imec leads 2D materials research, but Japan's approach has its own uniqueness. International collaboration could drive further progress.
Teaching at a university in Egypt. Fundamental semiconductor research is difficult in developing countries, but by learning from such research achievements, we hope to contribute in the future.
Researching at CEA-Leti in France. Low-power device applications are important from a climate change perspective too. This could help reduce data center power consumption.
Working at Intel's fab in Ireland. Introducing this to actual production lines requires reliability and yield verification. But as fundamental research, this is highly valuable.
Japanese engineer living in the US. Proud of my home country's research achievements. I hope Japan can leverage its materials science strengths to reclaim its position in the semiconductor industry.
Working at Ericsson in Sweden. 2D materials are also expected for high-frequency devices for 6G communications. Watching how Japan's research develops with great interest.
Researcher from Australia. Tokyo Electron's participation is interesting. Equipment makers being involved early could accelerate industrialization.