After a few days of rumors, it is now official. TSMC announced in a press release that it intends to build a chip factory in the United States, specifically in Arizona.

Construction is expected to begin in 2021 and the first chips from the fab could be manufactured in 2024. TSMC is the exclusive manufacturer of the A-series chips Apple uses in its iOS devices.

Apple has led the mobile industry in performance thanks to its shift towards designing custom chip silicon and getting TSMC to mass-produce its designs has also paid off in a big way. Several years ago, Apple shared orders between Samsung and TSMC, but TSMC has been the sole manufacturer for a while now.

Later this year, Apple will launch the iPhone 12 featuring the A14 chip. A14 will be fabricated on a 5-nanometer process, using TSMC’s latest engineering advances. In 2021, Apple and TSMC’s partnership will extend beyond iOS devices as the company begins to release Macs running on ARM chip architectures.

It is widely expected that Apple’s chip orders will eventually be fulfilled — at least partly — from the Arizona plant.

TSMC says the total spending on this project between 2021 and 2029 will be about $12 billion.