Samsung Electronics Co.’s surprise $16.5 billion chipmaking deal with Tesla Inc. has breathed new life into a foundry business all but written off by many investors.

Musk noted Tesla is working with TSMC to make AI5 chips, which just finished the design. The AI5, a generation that is primarily built for FSD, will initially be made in TSMC’s Taiwan factory and then at its Arizona facility. Samsung already makes the AI4 chip, according to Musk.