As you might remember, Huawei was placed on the U.S. Entity List in 2019 preventing it from accessing its U.S. supply chain. The following year, the U.S. made matters worse by using the Foreign Direct Product Rule (FDPR) to prevent Huawei from obtaining cutting-edge chips from foundries that use U.S. software and equipment to manufacture these components.
Why Huawei can’t obtain cutting-edge chips
The two major foundries producing chips using advanced process nodes both rely on American-made equipment and software. As a result, Huawei could not have its chips, designed by its HiSilicon unit, manufactured with the same high transistor density and transistor count as those produced by TSMC and Samsung Foundry. Chips with a high transistor density often have a high transistor count making them powerful and energy efficient.
At first, Huawei received approval to use special versions of Qualcomm’s Snapdragon application processors (APs) that were modified to work with 4G networks, not 5G networks. These are the flagship phones that used this workaround:
2021
- Huawei P50-Snapdragon 888 4G
- Huawei P50 Pro-Snapdragon 888 4G
2022
- Huawei Mate 50-Snapdragon 8+ Gen 1 4G
- Huawei Mate 50 Pro-Snapdragon 8+ Gen 1 4G
- Huawei P60-Snapdragon 8+ Gen 1 4G
- Huawei P60 Pro-Snapdragon 8+ Gen 1 4G
- Huawei Mate X3-Snapdragon 8+ Gen 1 4G
Since late 2023, Huawei has returned to equipping flagships and foldable phones with its own Kirin processors. | Image by Huawei
These machines transfer circuitry designs on the silicon wafers that chips are built on. The 13.5nm EUV wavelengths allow much thinner lines to be printed on the wafers allowing for higher transistor density. SMIC was allowed to own the previous generation of lithography machines called Deep Ultraviolet lithography, which features wavelengths of 193nm.
In 2023, Huawei produced its first 5G flagship phone since 2020
Why Huawei had to move away from traditional chip design
Huawei says that it will be able to design chips by 2031 that will have a transistor density equivalent to a 1.4nm chip. TSMC will start mass production of 1.4nm chips by the second half of 2028. While Huawei will still be behind by 2031, it will have closed the gap with leading foundries dramatically.
Huawei’s concept was presented Monday at the 2026 IEEE International Symposium on Circuits and Systems
The concept was presented by He Tingbo, president of Huawei’s semiconductor business during a keynote speech at the 2026 IEEE International Symposium on Circuits and Systems (ISCAS) in Shanghai on Monday. The Tau Scaling Law reduces the time it takes signals and data to move through chips and computing systems.
Huawei says that it has already used the Tau Scaling Law on 381 chips over the past six years. These chips were used for the smartphone and AI computing industries. Starting this fall Huawei will use LogicFolding, a related architecture that shortens wiring inside chips, to improve performance on Kirin chips.
Huawei has tried other ways to get around the U.S. sanctions including patenting its own advanced lithography machines. But so far it doesn’t appear to have been able to move forward in this direction. The Tau Scaling Law seems to have potential and appears to be Huawei’s best shot to obtain advanced process node chips.
