Even though SMIC is lagging behind TSMC and Samsung Electronics by 5-6 and 4-5 years, respectively, it still managed to cross the threshold of advanced semiconductor manufacturing by successfully manufacturing Huawei's Kirin 9000S processor with multiple exposure processes using its FinFET N+2 node on immersion DUV machines. However, the Kirin 9000S chip that SMIC produced for Huawei is not a "breakthrough." It is only a "breakout" of the restrictions imposed by the US.
Former TSMC R&D vice president Burn Lin, who invented immersion lithography technology, estimated chip production using multiple exposures with immersion DUV can be advanced to 5nm chips, at the maximum. However, it is very challenging to achieve an acceptable yield. SMIC is now trying to balance yield and capacity at the 7nm level. What is in front of it is a high wall, which is very difficult to scale, but giving up may not be an option for SMIC.
Another TSMC veteran, Liang Mong Song, took the helm in driving SMIC's FinFET chip processes from 28nm to 14nm and now successfully advanced to the N+1 and N+2 node of 7nm. But Liang, who was quite articulate in explaining plans to help SMIC overcome technical challenges during earnings release conferences before 2020, now has become reticent after the US imposed export restrictions on SMIC. Industry sources said SMIC's specifications must tolerate compromises such as lower clock, higher power consumption, and larger wafer area.
After disassembling the Huawei Mate 60 Pro, various parties found that the area of its heat sink covers almost the entire back panel of the phone, reflecting the fact that SMIC's advanced manufacturing process is still not mature enough, thus resulting in high heat, and the processor has to be downclocked. The question is, is this quality of smartphone AP good enough? How long will it last?
Before the US chip ban, Qualcomm had already lost major orders due to Huawei's self-developed 4G smartphone chips. The popularity of Huawei's Mate 60 Pro smartphones may also impact the sales of other competitors, including Xiaomi, Vivo, and Oppo, which have adopted the solutions of MediaTek. Would that affect MediaTek's foundry orders at TSMC?
What if SMIC managed to maintain a stable supply of the Kirin 9000S chips to HiSilicon, would Huawei stop purchasing chips from Qualcomm altogether? If Xiaomi and Honor, which are now using MediaTek and Qualcomm chips, continue their long-term effort in developing their proprietary chips and follow Huawei's steps to produce their own chips with SMIC foundry services? Will SMIC grab away Chinese manufacturers' foundry orders from TSMC and Samsung in the future?
At the beginning of the US export ban on SMIC, industry sources told DIGITIMES Asia that morale was low at the Chinese foundry service provider, seeing catching up with TSMC as a "mission impossible."
However, looking at SMIC's progress in hindsight, it seems the US restrictions prohibiting SMIC from accessing the most advanced semiconductor equipment did boost SMIC's incentive to try to prove its capability with the immersion DUV machines that they already had before the ban. Nevertheless, it is undeniable that SMIC will face tremendous difficulties trying to scale up amid the technological barriers at 7nm or even 5nm levels.
