Boosting the Future: Increased ALD Use Paves the Way for Advanced GAAFET Technology

The Biden administration is considering a complete ban on the export of chips utilizing Gate All-Around Field Effect Transistor (GAAFET) technology to China, Bloomberg reports (LINK). The rationale behind this potential ban is the concern that such advanced transistors could be leveraged for military applications and artificial intelligence (AI) advancements by China. This move follows previous restrictions from 2022, when the U.S. barred its Electronic Design and Automation (EDA) companies from selling tools necessary for GAAFET development to China. In addition, advanced chip exports from companies like Nvidia were restricted, with these measures being progressively tightened and expanded over time.

Atomic Layer Deposition (ALD) is celebrating its 50th anniversary in 2024. The anniversary marks 50 years since Dr. Tuomo Suntola and his colleagues filed the first patent for Atomic Layer Epitaxy in 1974, which laid the foundation for ALD technology. This milestone will be celebrated at various events, including the ALD 2024 conference, where Dr. Suntola is expected to deliver the opening remarks .

ASM International, a leader in Atomic Layer Deposition (ALD), plays a crucial role in enabling Gate-All-Around Field Effect Transistors (GAAFETs) and continued semiconductor scaling. ALD's precision in depositing ultra-thin, uniform films is essential for creating the high-performance, low-power structures required by GAAFETs. This technology, along with other advanced processes such as epitaxy and selective etching, supports the intricate fabrication steps needed for these next-generation transistors.

The production of GAAFETs requires a significant increase in the use of ALD technology - maybe up to 40% more according to ASM. ALD is essential for creating the ultra-thin, uniform films needed for GAAFET structures, ensuring high-quality, defect-free layers that are critical for advanced transistor performance. This technology enables precise control over the deposition process, crucial for developing high-k dielectrics and other materials that enhance GAAFET performance and efficiency. As the semiconductor industry now transitions from FinFET to GAAFET technology, leveraging ALD's capabilities is vital for maintaining and advancing Moore's Law, enabling more powerful and energy-efficient chips using existing manufacturing infrastructure

Applied Materials has outlined next-generation tools essential for producing 3nm and GAA transistors, such as those in Samsung's upcoming 3GAE and 3GAP technologies. These advanced tools address the complexities of GAA transistor manufacturing, including precise lithography, epitaxy, and selective materials removal. Applied's Producer Selectra Selective Etch IMS tool is pivotal in defining channel width without damaging surrounding materials, while the Centura Prime Epi tool ensures clean deposition of Si and SiGe nanosheets. Additionally, their Integrated Materials Solution (IMS) systems integrate atomic layer deposition (ALD), thermal steps, and plasma treatments to optimize the gate oxide stack, enhancing performance and reducing gate leakage. These innovations are crucial as they enable higher performance, lower power consumption, and greater transistor density, aligning with the industry's move from FinFET to GAA technology.

Today GAA transistors are currently in mass production only by Samsung, which offered the technology to customers with its 3-nanometer process in 2022. Intel is set to follow, producing GAAFET on its 2-nanometer process expected to be available in its products later this year. TSMC, the market leader, plans to introduce GAAFET with its own 2 nm process in 2025. The GAAFET technology itself is not inherently suited for AI or military applications but represents an evolution in transistor design, enabling denser packing of transistors as lithography equipment and manufacturing processes advance. This technology shift, akin to transitioning to a new node, typically results in either reduced power consumption or improved performance by 15-25%.

The improvements facilitated by GAAFET could significantly enhance the capabilities available to China. SMIC, China's largest contract manufacturer, currently produces chips on a 7 nm process and is believed to be capable of reaching at least 5 nanometers with existing tools. The combination of this process with GAAFET could theoretically prevent China from falling too far behind Western advancements. However, China has been effectively shut out from developing GAAFET using tools from leading EDA companies, all of which are American. Additionally, the Dutch company ASML, dominant in the lithography equipment market, has not sold its EUV (Extreme Ultraviolet) machines to China and faced further restrictions in 2023 on selling its advanced DUV (Deep Ultraviolet) equipment. In April 2024, ASML took another step in the tech war against China by announcing that it would no longer service existing equipment in China, potentially crippling the country's semiconductor manufacturing capabilities. The specific details of the new export bans are still unclear, but Reuters notes that initial proposals have faced criticism from the U.S. semiconductor industry for being overly broad and extensive.

Source: USA överväger ytterligare GAAFET-sanktioner mot Kina – Semi14, www.ASM.com, Applied Materials Outlines Next-Gen Tools for 3nm and GAA Transistor Era (anandtech.com), Atomic layer deposition, next-gen transistors, and ASM (techfund.one)