The United States is intensifying its measures to restrict China’s access to cutting-edge chip technologies capable of manufacturing gate-all-around (GAA) transistors and high-bandwidth memory (HBM) chips.
ChangXin Memory Technologies Inc (CXMT), a Hefei-based company that manufactures DRAM for computer servers and smart vehicles, is likely to be a significant focus of Washington’s potential restrictions, as per media reports. Samsung Electronics, SK hynix, and Micron are among the major competitors of CXMT.
Alan Estevez, who heads the Bureau of Industry and Security (BIS) at the US Commerce Department, recently embarked on a trip to the Netherlands. The purpose of his visit, as reported by Reuters on Tuesday, was to discuss the inclusion of an additional 11 Chinese chip manufacturing facilities to a restricted list. Following this, Estevez proceeded to Japan to engage in similar discussions.
On Wednesday, Bloomberg reported that Estevez’s objective is to persuade the governments of Japan and the Netherlands to impose further restrictions on shipments to China from Tokyo Electron Ltd and ASML, respectively. Estevez’s ongoing conversations with allies are expected to underscore the development of high-bandwidth memory (HBM) chips by Chinese chip factories, which have potential applications as accelerators in the field of artificial intelligence (AI).
Last month, Reuters revealed that CXMT and XMC, a subsidiary of YMTC, are in the initial phase of HBM chip production, seeking tools from South Korea and Japan. CXMT has teamed up with Tongfu Microelectronics to create HBM chip samples and has presented them to customers. Meanwhile, XMC started building a facility in February capable of producing 3,000 12-inch HBM wafers monthly.
At present, five Chinese semiconductor manufacturers, namely Huawei Technologies, Semiconductor Manufacturing International Corp (SMIC), and Yangtze Memory Technologies Co (YMTC), have been placed on the US Entity List. As reported by Bloomberg in March this year, Washington is contemplating the addition of CXMT and five other Chinese chip manufacturers to the blacklist.
Last December, CXMT piqued the interest of the Bureau of Industry and Security (BIS) when it announced progress in its development of Gate-All-Around (GAA) chip technology. During the 69th IEEE International Electron Devices Meeting (IEDM) held in San Francisco, CXMT unveiled a paper demonstrating a GAA technology suitable for state-of-the-art 3nm chips.
The South China Morning Post published an article suggesting that the design of CXMT’s GAA chips might incorporate technology that falls under US export restrictions. However, CXMT clarified that the research is unrelated to its current production processes and firmly stated that any allegations of CXMT violating US export controls are entirely unfounded.
Historically, semiconductors were composed of planar transistors, also known as MOSFETs. These faced issues of current leakage and heat dissipation when scaled below the 28nm process node. To address this, Intel introduced the fin field-effect transistors (FinFETs) in 2011. These transistors have a vertical “fin” added to each gate, mitigating the current leakage problem. However, as chip sizes continue to shrink, the issue re-emerges.
This led to the development of GAAFET technology, which transforms the “fin” into a nanowire or nanosheet. This technology enhances the performance of semiconductors and reduces their power consumption. It is applicable to chips of 5nm, 7nm, and 14nm sizes.
In June 2022, Samsung initiated the large-scale production of its 3nm chips based on GAA technology. Subsequently, in August 2022, the Bureau of Industry and Security (BIS) declared a new regulation prohibiting the export of American electronic design automation (EDA) software, a tool essential for designing GAA chips, to China. The methods employed by CXMT in its GAA research remain ambiguous.
According to a Bloomberg report on June 11, the Biden administration is currently considering imposing additional limitations on China’s access to GAA technology. Lin Jian, a spokesperson for the Chinese Foreign Ministry, stated on June 12 that while the US expresses a desire for AI dialogue with China, it is also contemplating measures to target China’s AI sector. Lin criticized the US, referring to it as hypocritical. He further emphasized that China’s technological advancement will not be impeded by these actions, but rather, it will serve as motivation for Chinese companies to excel by relying on their own capabilities.
“US sanctions haven’t stopped China’s chip advancements, instead prompting self-reliance in the entire industry,” says Xiang Ligang, Information Consumption Alliance’s director-general. He criticizes the US’s futile, shortsighted attempts to limit China’s chip-making. Yet, concerns arise among Chinese columnists about the long-term impact of the GAA technology export ban on China’s chip-design capabilities. An anonymous writer, highlights in a June 15 article that significant strides have been made in the “vertical sandwich GAAFET” development by Zhu Huilong’s team at the Chinese Academy of Sciences’ Institute of Microelectronics, besides CXMT. He warns that if the US intensifies GAA technology export controls, it could pose greater challenges for Chinese fabless chip makers in future 3nm chip design. He urges Chinese chip makers not to downplay the potential adverse effects of this possible restriction.