Micron Breaks Ground on ¥1.5 Trillion Hiroshima Fab Expansion as Japan Pledges Up to ¥500 Billion for AI Memory
Micron broke ground on July 4 on a ¥1.5 trillion ($9.3 billion) expansion of its Hiroshima fab to scale next-generation DRAM and HBM for AI, with Japan's METI pledging up to ¥500 billion in subsidies and equipment installation set to begin in the second half of 2028.
Overview
Micron Technology broke ground on July 4 on a ¥1.5 trillion (US$9.3 billion) expansion of its memory fab in Hiroshima, Japan, according to TrendForce. Equipment delivery and installation are set to begin in the second half of 2028, as reported by TrendForce and Yahoo Finance. Japan’s Ministry of Economy, Trade and Industry (METI) is pledging up to ¥500 billion in subsidies for the project, per TrendForce.
What We Know
The site anchors Micron’s leading-edge DRAM. The Hiroshima site already serves as a key production base for Micron’s 1β (one-beta) DRAM and was the first to introduce EUV lithography for the company’s 1γ (one-gamma) node, according to TrendForce. Micron deployed an EUV lithography machine at the Hiroshima site in May 2025, after announcing plans in 2023 to invest up to $3.6 billion to bring EUV to Japan, as reported by Data Center Dynamics.
HBM4 is already in mass production. Micron’s HBM4, designed for NVIDIA’s Vera Rubin platform, has already entered mass production, with scaling planned from the current 1β node to the 1γ process, according to TrendForce. In March, Data Center Dynamics reported that Micron had commenced volume production of HBM4 36GB 12H memory for the Vera Rubin platform, delivering over 2.8 TBps of bandwidth — 2.3 times greater than previous-generation HBM3E with equivalent capacity and stack height. The company has also shipped HBM4 48GB 16H samples to customers, a 33 percent capacity increase over the 36GB 12H variant, per Data Center Dynamics. The industry-wide HBM4 ramp toward Vera Rubin was previously reported by The Machine Herald.
1γ products are moving through qualification. During its fiscal third-quarter 2026 earnings call, Micron disclosed that qualification samples of its 1γ-based 256GB DDR5 RDIMM had been shipped to major server ecosystem partners, while mass production of 1γ 16Gb LPDDR5X had begun for leading smartphone OEMs, according to TrendForce.
Hiroshima carries symbolic weight for Micron. “Micron’s first-ever HBM production wafer was made right here in Hiroshima,” Chief Executive Officer Sanjay Mehrotra said at the groundbreaking event, as reported by TrendForce, which cited Bloomberg’s coverage of the ceremony. About 80% of the chip materials used at Micron’s Hiroshima fab come from Japan, per TrendForce.
The project was first reported as a $9.6 billion plan. When the expansion surfaced in December 2025, Data Center Dynamics, citing Nikkei Asia, put the planned investment at $9.6 billion, with METI expected to contribute up to $3.2 billion in subsidies, construction to begin in May 2026, and first shipments of HBM chips produced at the site expected from 2028. According to the same report, Nikkei Asia estimated METI’s total subsidies to Micron at up to $5 billion.
What We Don’t Know
- The cited coverage does not specify wafer capacity, output targets, or how the new space will be divided between DRAM and HBM production.
- The shipping timeline for the new lines is not fully settled in the cited reports: the December report from Data Center Dynamics, citing Nikkei Asia, said first HBM shipments from the site were expected from 2028, while TrendForce reports that equipment delivery and installation will begin in the second half of 2028.
Analysis
The groundbreaking lands in the middle of a regional capacity race. It came shortly after South Korea’s memory makers unveiled a combined 800 trillion won investment to expand capacity, according to TrendForce. Samsung plans to fully operate its P4 fab in Pyeongtaek this November, followed by phased ramp-ups of P5-1 in 2028 and P5-2 in 2030, while SK hynix targets full operation of its M15X fab in Cheongju by 2027 and plans to start construction of M17 next year, with production slated for the first half of 2029, per TrendForce. The Machine Herald previously reported on SK hynix’s 100-trillion-won Cheongju commitment.
For Micron, the Hiroshima build is also a competitive play: the company reportedly hopes the facility will allow it to catch up to SK Hynix, the current market leader in HBM, as Data Center Dynamics reported in December.
The timing cuts both ways. Semiconductor fabs typically require at least three years from groundbreaking to equipment installation and yield stabilization, and TrendForce notes that this timing gap has fueled concerns the industry could face oversupply if demand softens as new capacity comes online across multiple regions.