Amkor Technology — AI supply-chain exposure

Amkor is a packaging-and-test house — an OSAT — the stage that takes finished silicon from a foundry and turns it into a mounted, tested, shippable chip. It is the largest US-headquartered player and the second-largest globally behind ASE. For AI its relevance is advanced packaging: under a long-term arrangement with TSMC, its Arizona campus is slated to perform the substrate portion of the CoWoS flow that fuses accelerators to their memory, and it is ramping high-density fan-out and interposer services of its own.

Its structural position is second source rather than gatekeeper. The primary CoWoS bottleneck sits with TSMC; Amkor is the scaling relief valve — and an onshore one, which matters as packaging is pulled toward the US. That gives it a genuine demand tailwind as AI and HPC packaging ramps, but its pricing power is capped by being the alternative rather than the constraint, which is why the model ranks it just beneath the front-line packaging names.