- Chinese researchers have developed an early sub-3nm GAA transistor process.
- The technology remains at an early stage and cannot yet support commercial production.
- The GAA architecture improves current control, replacing FinFET designs.
- Export restrictions have led China to explore the potential of older DUV equipment.
Chinese researchers have developed an early process for building gate-all-around (GAA) transistors at sub-3nm using deep ultraviolet (DUV) lithography, potentially giving China an alternative path to advanced chip manufacturing in the absence of cutting-edge extreme ultraviolet (EUV) machines. According to a Digitimes report, the work is based on comments by veteran Chinese semiconductor researcher Ye Tianchun. As U.S. and Dutch export restrictions continue to limit China's access to ASML's most advanced lithography systems, the Chinese Academy of Sciences (CAS) said its researchers had completed early-stage work integrating stacked nanosheet-channel GAA CMOS transistors using DUV tools.
However, the technology remains at an early stage of development and has not yet demonstrated the ability to support commercial-scale production.
Advantages and challenges of GAA technology
The GAA architecture helps overcome lithography limitations. The research focuses on GAA transistors, an architecture that replaces FinFET designs as semiconductor manufacturers push toward smaller process nodes. Unlike FinFETs, whose gates surround the transistor channel on three sides, GAA designs wrap the gate all the way around the channel, offering greater control over current flow. The South China Morning Post reported that the CAS team has integrated stacked nanosheet-channel GAA CMOS transistors using DUV lithography.
Ye Tianchun, a senior researcher at the CAS Institute of Microelectronics, described the work as an early process pathway for developing sub-3nm devices. However, this does not mean China has demonstrated producible sub-3nm chips. The researcher stressed that the work remains at an early stage and requires further wafer-level validation to determine whether the process can ultimately be transferred to a production line.
Background on China's semiconductor development
Nonetheless, the approach carries significance because GAA technology has already been adopted by leading semiconductor manufacturers. Samsung has begun mass-producing 3nm chips using GAA technology, while TSMC plans to adopt the architecture for its 2nm process in 2025. The research is set against the backdrop of China's limited access to extreme ultraviolet (EUV) lithography, which leading chipmakers use to produce the most advanced semiconductor nodes. ASML's EUV machines use 13.5nm light to pattern extremely fine features on silicon wafers.
These systems are among the most complex industrial machines ever built and are essential to the production of today's cutting-edge chips. Export restrictions prevent ASML from selling EUV systems to Chinese customers, so Chinese semiconductor researchers are increasingly exploring how to extract more performance from older DUV equipment — including through new transistor structures, process techniques and materials.
The Chinese Academy of Sciences is working on several pieces of this puzzle. In 2025, researchers at the institute developed an all-solid-state DUV laser capable of producing 193nm coherent light, the wavelength used by advanced DUV lithography systems. Researchers are also investigating whether different equipment architectures and process techniques can compensate for lithography limitations. Still, China's semiconductor industry is pursuing several parallel solutions. In 2026, Huawei introduced what it calls the Tau Scaling Law, a chip design methodology based on "time scaling" that the company says could ultimately deliver transistor densities comparable to a 1.4nm process by 2031.
Future challenges for China's semiconductor technology
China faces export-control challenges in semiconductors, particularly in acquiring advanced extreme ultraviolet (EUV) lithography technology. This has forced researchers to seek alternatives, such as using deep ultraviolet (DUV) technology to develop new types of GAA transistors. Although the current technology remains at an early stage, its potential implications are significant, especially as global semiconductor competition intensifies. With other leading players such as Samsung and TSMC already using GAA technology, China's research progress could influence the future market landscape.