Micron breaks ground on a $9.3B Hiroshima expansion for HBM

Micron broke ground on a ¥1.5 trillion ($9.3B) expansion of its Hiroshima plant to produce advanced memory including the high-bandwidth memory used in AI processors. Equipment installation is scheduled for the first half of 2028, with shipments around summer 2028. Japan's METI has allocated up to ¥500B toward the project — bringing government support for Micron in Japan to roughly ¥775B — alongside Micron's US buildout (two Boise fabs and the $100B Syracuse site).

Why it matters

This is the memory-shortage thesis converted into concrete: after guiding that the shortage runs past 2027 and signing GM as a direct supply customer, Micron is now adding HBM capacity on a 2028 clock — and Japan is paying a third of the bill to host it. It also deepens the geographic split of AI-memory capacity across Japan, Korea (SK hynix's ₩100T Cheongju plan) and the US.

What to watch

Whether the 2028 shipment date holds, and HBM customer allocation — how much of the new capacity is pre-sold before the tools are even installed.