Samsung HBM4E Yield Exceeds 70% as 7th-Gen AI Memory Development Stabilizes
Taylor Wilson
Samsung's seventh-generation high-bandwidth memory HBM4E has crossed 70% in reliability-test yield — still short of the 80% mass-production threshold, but converging fast. Whether Samsung can lock in its slot in Nvidia's next-gen AI accelerator supply chain is now the central question.
What does a 70% yield actually mean?
Samsung CTO Song Jai Hyuk disclosed at an internal DS-division briefing that HBM4E — the seventh-generation high-bandwidth memory — has passed 70% reliability-test yield.
The industry treats 80% as the "mature yield" line. This means → HBM4E is not there yet, but it has moved from the debugging phase into the ramp-toward-production zone.
In plain terms = seven out of ten chips pass testing. Not stable enough to ship at scale, but the trajectory is right and accelerating.
Which chip is HBM4E destined for?
On Nvidia's roadmap, HBM4 goes into the Vera Rubin AI accelerator launching in the second half of this year; HBM4E, its successor, is slated for Vera Rubin Ultra next year.
This means → Samsung's yield ramp on HBM4E directly determines whether it secures a seat in Nvidia's next-generation supply chain.
Samsung began mass-producing sixth-gen HBM4 in February, released detailed specs for the 12-layer HBM4E on May 29, and shipped samples to key customers. Sample evaluation is underway.
Why does D1d matter?
Song also revealed that Samsung's next-gen 10nm-class seventh-generation DRAM process, D1d, is targeted to clear Production Readiness Assessment (PRA) — the final internal quality gate before mass production — by November.
Samsung plans to adopt D1d across the board starting with eighth-gen HBM5. This means → D1d is not just a single-chip process upgrade; it is the foundation for the entire HBM product line's next competitive cycle.
In plain terms = D1d is the foundation for next-gen HBM. If the foundation fails, nothing built on top holds up.
Could internal pay disputes slow things down?
After the briefing, discontent among DS-division R&D staff over role classification and pay structure reportedly intensified.
Management and labor had already agreed to fund a "special performance bonus" pool at 10.5% of operating profit, but the gap between memory-division bonuses and those for shared units such as the research institute — and for non-memory businesses — remains wide. Calls for structural pay reform are growing.
This reflects a two-front challenge for Samsung: a technology catch-up race and an organizational stability question running in parallel. Whether R&D momentum can stay insulated from internal friction is an underappreciated risk.
What to watch next?
Milestone one: can HBM4E yield cross the 80% maturity threshold before mass production?
Milestone two: can D1d clear PRA certification in November on schedule?
In plain terms = these two gates are Samsung's final exams for next-gen AI memory competitiveness — nothing counts until they pass.
Content is for reference only, not financial advice.