China’s Breakthrough in 2D Semiconductor Technology: A Step Toward Self-Reliance

Chinese researchers have developed the world’s most advanced 2D semiconductor microprocessor, Wuji, a 32-bit RISC-V chip with 5,900 transistors and less than 1nm thickness. Unlike traditional silicon chips, Wuji uses 2D materials and avoids EUV lithography, achieving high precision and a 99.77% yield. Built on open-source architecture, it integrates with existing silicon production lines, advancing China’s self-reliance in semiconductors. While complementing silicon chips, Wuji positions China as a frontrunner in next-generation semiconductor innovation. 

Chinese researchers have achieved a significant milestone in semiconductor technology by developing the world’s most complex two-dimensional (2D) semiconductor microprocessor. This groundbreaking innovation, detailed in Nature on Wednesday, showcases a 32-bit RISC-V microprocessor named Wuji, built using 2D materials and measuring less than one nanometer thick. The chip is now preparing for pilot-scale production, marking a new chapter in China’s pursuit of technological self-reliance.

Pioneering a New Path for Chip Fabrication

Unlike conventional silicon chips, Wuji was fabricated without the use of extreme ultraviolet (EUV) lithography, a cutting-edge but resource-intensive technology. This achievement paves the way for an alternative pathway in chip manufacturing, offering a potential solution as silicon-based circuits approach the physical limits of miniaturization.

Researchers worldwide have long been exploring 2D materials, such as molybdenum disulfide and tungsten diselenide, for their unique physical properties. These materials, often just one atom thick, promise enhanced performance and scalability for next-generation integrated circuits. However, the challenges of working with such fragile materials have historically limited the complexity of 2D semiconductor circuits. Until now, the most advanced 2D chip, developed in 2017, contained just 115 transistors.

A Leap Forward in Integration and Efficiency

The team from Fudan University, led by Professors Bao Wenzhong and Zhou Peng, spent five years developing Wuji, which incorporates 5,900 transistors – over 50 times more than its predecessor. This breakthrough was made possible by achieving atomic-scale precision and uniformity, ensuring high manufacturing yields.

Key to the chip’s success was the development of highly efficient inverter circuits, the fundamental building blocks of chips. “The inverters we created with 2D materials showed excellent signal output and minimal energy loss when turned off,” Zhou explained. Testing of 900 inverters revealed a record yield of 99.77%, with superior switching voltage and consistency compared to earlier studies.

The fabrication process was optimized using artificial intelligence, refining steps from material synthesis to integration. This builds on the team’s earlier achievements, including the growth of monolayer molybdenum disulfide on 12-inch wafers in 2023.

Open-Source Architecture and Domestic Innovation

Wuji is built on the open-source RISC-V architecture, which aligns with international standards while avoiding reliance on proprietary intellectual property. Professor Han Jun, a co-author of the research, highlighted the benefits of this choice: “RISC-V allows us to create a fully autonomous ecosystem without the constraints of foreign vendors’ patents.”

Wuji’s capabilities are impressive. Operating under a 32-bit instruction set, the chip can handle up to 4.2 billion data units, support gigabyte-scale data storage, and execute programs with up to 1 billion RISC instructions. Approximately 70% of its fabrication steps can be integrated into existing silicon-based production lines, while the remaining processes were developed domestically, supported by over 20 invention patents.

Professor Bao likened the development process to repurposing parts of a building: “The foundation and structure remain the same, but some sections are redesigned to meet unique requirements.”

Implications for China’s Semiconductor Industry

The Wuji chip represents a significant step forward for China’s semiconductor industry, which has faced challenges in accessing advanced technologies due to geopolitical constraints. By leveraging domestically developed equipment, the open-source RISC-V framework, and innovative 2D integration techniques, China is forging a new path toward self-reliance.

Looking ahead, Zhou emphasized that 2D semiconductors are not intended to replace traditional silicon chips but to complement them. Wuji is compatible with existing interfaces and can be deployed in a wide range of current applications.

Globally, research into 2D semiconductors remains in its early stages, with commercial applications still on the horizon. However, this achievement positions China as a potential leader in the next frontier of semiconductor innovation, bridging the gap between today’s limitations and tomorrow’s possibilities.

Source: This article is based on reporting from the South China Morning Post (SCMP).