I question the amount of secret stealing that could effectively occur in the factory itself. Tool parameters can be loaded over encrypted networks directly from secure systems. Reticles at 7nm and lower nodes are hopelessly impossible to reverse-engineer. Tool operator interfaces can be locked down to provide only the most essential information. What exactly are you going to pilfer from these factories? Everyone knows you buy EUV from ASML. Not a whole lot of insight to be gleaned by just observing operations. Sure, you could decide that IP exfiltration is not going to work and resort to sabotage. Causing defects intentionally is not very difficult, but I doubt you would get away with it for very long. The amount of measuring, logging and tracking that occurs throughout is beyond incredible. Everything is a consideration in the hopes of squeezing out more yield. As a consequence, you have the best audit log in any business on earth.
I've worked in the industry and you can't even go inside the lobby of one of these buildings without having epoxy poured into all the USB ports of your various electronics. Security is best described as absolute in these facilities. Getting into the factory itself is yet another security check. You cannot bring any personal items into the clean room last I was told the rules.
I know but what if TSMC had to apply possible US sanctions against China? First, TSMC would be a US company, which could give the USA an excuse to tell TSMC to apply sanctions against China. Also, the USA could take the US factory.
The US already has that ability to coerce foreign companies. TSMC buys chip making supplies and equipment from US companies, and there's been discussions around requiring foreign companies using US technology to obtain a license to not supply chips to Huawei or risk getting cut off from the US tech network themselves.
I've worked in the industry and you can't even go inside the lobby of one of these buildings without having epoxy poured into all the USB ports of your various electronics. Security is best described as absolute in these facilities. Getting into the factory itself is yet another security check. You cannot bring any personal items into the clean room last I was told the rules.