An advanced packaging facility instead of Fab 21 phase 6?
(Image credit: TSMC)
One of the caveats of TSMC's manufacturing in the U.S. is that all wafers processed at Fab 21 in Arizona are shipped back to Taiwan for dicing, testing, and packaging, which is why processors fabbed in Arizona are not 100% U.S.-made. However, suppose the rumor published by Taiwan-based Liberty Times is correct. In that case, TSMC is repurposing land designated initially for one of its Fab 21 modules for its advanced packaging facility, thus accelerating its packaging capability in the U.S. and making 'all American TSMC chips' a reality before 2030.
Based on the latest expansion plan for the Arizona site announced in March, TSMC plans to build six Fab 21 modules, two advanced packaging facilities, and an R&D center to work on the foundry's existing technologies and tailor them for specific customers. Liberty Times claims that TSMC now intends to build its advanced packaging facility on the place originally intended for the Fab 21 phase 6. If construction proceeds according to the alleged plan, tool move-in could begin before the end of 2027, enabling the plant to enter a risk production phase shortly thereafter.
Even though modern advanced packaging facilities use cleanrooms and many tools that were used for chipmaking years ago, they are very different from advanced semiconductor production facilities, such as TSMC's Fab 21. Front-end fabs require huge, hyper-clean, multi-story cleanrooms to support atomic-scale patterning. In contrast, advanced packaging needs much smaller, lower-class spaces suitable for micron-scale bonding and RDL processes. Even state-of-the-art packaging facilities feature significantly smaller ISO 5-7 class cleanrooms compared to ISO 3-4 class cleanrooms in advanced fabs. Also, advanced packaging fabs require much lower chemical purity and use less power (unless we are talking about a massive facility, though).
That said, building an advanced packaging facility close to an advanced front-end fab makes a lot of sense. However, building an advanced packaging facility next to five phases of an advanced fab complex, rather than its sixth phase, does not look like a great idea, as the site is currently being developed with six fab phases next to each other in mind. Unless, of course, TSMC must build an advanced packaging facility in the U.S. before the end of 2027 and then initiate chip packaging shortly thereafter. That necessity could be driven by various issues, including demands from specific customers, an appeal to reduce potential risks associated with chip tariffs, or other factors outside the traditional supply-demand scope.
Alongside its own expansion plans, TSMC maintains a partnership with Amkor, which is set to become one of the major OSAT providers in the United States once its Arizona facility ramps up towards the end of the decade. Amkor is currently building an assembly and test factory near TSMC's Arizona hub, with Apple as the anchor customer, and plans to start production there in 2028. This cooperation remains part of TSMC's long-term strategy, but the timing is not aligned with the company's requirements. Consequently, the decision to accelerate the in-house advanced packaging project on the phase 6 allotment effectively brings backend capacity online earlier than the partner-driven route would allow.
Tom's Hardware has asked TSMC for a comment. However, we do not expect the company's public relations to delve into details about its plans for its advanced packaging facility in Arizona at this point, but rather to wait for its chief executive to comment during the upcoming earnings call in January.
Anton Shilov is a contributing writer at Tom’s Hardware. Over the past couple of decades, he has covered everything from CPUs and GPUs to supercomputers and from modern process technologies and latest fab tools to high-tech industry trends.
