Worse, Huawei’s main production partner, Semiconductor Manufacturing International Corp., is struggling to churn out even 7nm chips at steady volumes. The Shanghai-based firm’s 7nm production lines have been plagued by poor yield and reliability issues, according to another person. There’s little guarantee that Huawei will be able to secure enough smartphone processors and AI chips in coming years, the person added.

That quote is disproven by the fact that you can order Huawei phones which contain 7nm chips. If they weren’t “able to secure enough smartphone processors” the phones would be sold out, as they couldn’t produce enough. You can call that low demand or whatever, but it seems obvious that they can produce enough 7nm chips to satisfy their customer needs.

State-backed chipmakers have been trying to push the limit of ASML’s older deep ultraviolet lithography machines, the Dutch supplier’s second-best lineup (after EUVs), with the so-called quadruple patterning technique.

That requires lithographic machines to perform up to four exposures on a silicon wafer, with a total margin of error of no wider than hundredths the diameter of a human hair. Compared to EUV lithography, the multi-patterning technique with DUVs is not only resource-intensive but also prone to alignment errors and yield losses, according to Ying-Wu Liu, an analyst at research firm Yole Group.

Yes, multiple patterning techniques are not the most efficient, but they are pretty much required to work with these sizes. This is proven by the fact that every single company that makes 7nm and lower makes use of multiple patterning (TSMC, Samsung, Intel). Huawei’s problem is that they have old ASML equipment (DUV), which is enough for their customer demands at 7nm, but starts showing its age at smaller nodes.