[News Terms] US Emerges 'GAA' as Key Card in Semiconductor Sanctions Against China

The Gate-All-Around (GAA) technology, which the U.S. government is considering as an additional sanction measure against China's semiconductor industry, is a technology that overcomes the limitations of the existing dominant semiconductor transistor structure, FinFET.

A transistor is a key component that makes up semiconductors, functioning to amplify or switch by controlling the flow of current. The most important part of this transistor is the gate. When voltage is applied through the gate, current flows; in the opposite case, the current is blocked. As the size of semiconductors shrinks and integration increases in the AI era, the size of transistors in a single semiconductor chip is also getting smaller. At this time, the need to precisely control the smaller transistors led to the development of FinFET technology, a three-dimensional (3D) process technology. Because its structure resembles a fish fin, it is also called a "fin transistor." The gate and channel contact on three surfaces, increasing the contact area to improve semiconductor performance. Samsung Electronics applied fin transistors starting from the 14 nm (nanometer; 1 nm = one billionth of a meter) process in 2012.

However, this method was identified as having limitations in applying to processes beyond 4 nm. Therefore, the next-generation 3 nm GAA structure evolved into a form where all four surfaces are in contact. The GAA transistor structure features gates surrounding all four sides of the current-carrying channel, allowing more precise control of current flow. For processes below 3 nm, GAA is known to be more efficient than FinFET.

Samsung Electronics introduced GAA to its 3 nm foundry (semiconductor contract manufacturing) process for the first time in the industry in 2022. Other foundry companies such as Taiwan's TSMC and Intel have also announced plans to adopt GAA for processes below 2 nm.

Meanwhile, Bloomberg News reported on the 11th (local time), citing multiple sources, that the U.S. government is discussing blocking China's access to GAA technology, which is considered next-generation transistor technology. The U.S. Department of Commerce’s Bureau of Industry and Security (BIS) recently sent a draft of GAA regulations to a technical advisory committee composed of industry experts, and this procedure is said to be the final step before the introduction of regulations, although it has not yet been finalized. The semiconductor industry is closely watching which direction the GAA regulation discussions will take.