Micron’s 2028 HBM Plant Arrives Three Years Behind SK Hynix

Published by James Harris on July 4, 2026July 4, 2026

Micron broke ground on a $9.3 billion memory chip plant in Hiroshima, with production of high-bandwidth memory targeting AI accelerators not expected to begin until approximately summer 2028. Japan’s Ministry of Economy, Trade and Industry is contributing up to roughly $3.1 billion toward the facility, part of a broader government push to build domestic semiconductor capacity.

The timing matters more than the headline number. AI labs are now locking in memory supply years before they need it, which reflects how completely the HBM market has flipped from a commodity dynamic to a strategic one. Micron enters this race from third place: a report citing Counterpoint Research put SK Hynix at roughly 57% of the global HBM market at end of 2025, with Samsung and Micron at approximately 22% and 21% respectively. SK Hynix is already shipping 12-layer HBM4E samples with over 20% energy savings versus prior generations, and Samsung has begun sending HBM4E samples to customers while publishing roadmaps for HBM5. Micron’s Hiroshima facility, by contrast, won’t produce a single chip until 2028, meaning it is essentially pre-selling capacity that doesn’t exist yet into a market that may look quite different by then.

Micron’s Q3 fiscal 2026 revenues hit a record $41.46 billion, up from $9.30 billion in the same period a year earlier, which makes the scale of what’s at stake legible without any further commentary.

Two days before the groundbreaking, Micron signed a strategic agreement with Anthropic covering memory architecture design, a multi-year supply contract, and an investment in Anthropic’s Series H financing. That deal is the actual signal here: it demonstrates that memory producers are now functioning as infrastructure partners to AI labs rather than commodity suppliers, and that long-term contracts are being signed well ahead of production capacity coming online. South Korea’s government recently announced an $518 billion public-private initiative with Samsung and SK Hynix to double domestic DRAM output and expand HBM packaging, which means the competitive pressure on Micron is state-backed, not just commercial. The Samsung and SK Hynix antitrust exposure in US courts adds a layer of uncertainty to that duopoly’s dominance, though it is unlikely to slow either company’s capital deployment in the near term.

Nikkei Asia previously reported on Micron’s interest in Japan’s manufacturing infrastructure, so this groundbreaking is less a surprise than a confirmation of a strategy that has been building for some time. The operating margins for Micron’s Cloud Memory Group and Core Data Center Group, at 78% and 83% respectively, suggest the company has the financial headroom to absorb the multi-year wait. Whether the market structure in 2028 still rewards a third-place player with a brand-new plant is the question none of today’s announcements can answer.