DRAM Architecture Competition: Divergent Paths Between CXMT’s 4F² Innovation and Micron’s 3D Roadmap

      Recent technical announcements in the DRAM sector have unveiled two distinct development strategies, triggering wide industry discussions on the evolution path of next-generation DRAM.

      CXMT announced key R&D progress on its self-developed 4F² cell architecture, and plans to launch server-grade DDR5 RDIMM modules adopting this design together with hybrid bonding technology by the end of 2026. The news reshaped market expectations for long-term high-end memory supply, leading to sharp swings across global memory stocks. Korean memory leaders, Micron and Japanese flash vendors all faced share price corrections, prompting reassessment of long-term DRAM competition and cost curves.

      At its 2026 Technology Symposium, Micron shared its technical conclusion. Based on over two decades of research, Micron stated that 4F² DRAM faces inherent challenges in engineering complexity and manufacturing cost, with no viable path toward large-scale commercialization. Micron will suspend 4F² development, and adopt a dual strategy: continuously optimizing the mature 6F² architecture, while prioritizing 3D DRAM as its core next-generation direction.

      One route represents a promising structural breakthrough for China’s memory maker, while the other reflects a well-validated strategic pivot from a global giant. The two choices mark separate ways for DRAM to break through after hitting physical scaling limits.

      To understand this divergence, it is necessary to review the fundamentals of DRAM cells. For decades, mainstream DRAM relies on the 6F² planar cell design, where F stands for feature size. Smaller cell area means higher bit density per wafer and lower cost per bit. Historically, DRAM cost reduction was mainly driven by process scaling.

      As nodes move below 10nm, planar scaling hits physical boundaries. Shrinking cell capacitors make leakage increasingly difficult to control, and lithography approaches precision limits. The industry has two directions: further compressing planar cells into 4F², or adopting vertical stacking via 3D DRAM. Micron and CXMT have chosen these respective tracks.

      Micron’s roadmap builds upon its existing mature process ecosystem, extending 6F² iteration while investing heavily in 3D DRAM and 3D integration for peripheral CMOS circuits. Key milestones for its 6F² evolution are clear:

• The 1γ node is in high-volume production with EUV lithography introduced for the first time.
• The 1δ node, the seventh-generation 10nm-class DRAM, is in yield ramp-up and scheduled for mass production in H2 2027. It is Micron’s first advanced node manufactured domestically in the US, delivering roughly 25% higher density versus 1γ, and supporting HBM5, next-gen DDR, LPDDR and graphics memory.
• The 1ε node is under development with wafer bonding.
• The ζÅ sub-10nm node is in early development, equipped with High-NA EUV.
• The ηÅ node remains in exploratory research with new material options.

      For 3D DRAM, Micron has outlined 3D1 and 3D2 generations, using vertical stacking to bypass planar scaling limits. It also pushes 3D CMOS logic integration, targeting a 10× performance gain for logic circuits by 2030, to underpin its competitiveness in AI memory.

      Micron’s strategy focuses on incremental advancement with its full suite of advanced manufacturing tools including EUV and High-NA EUV. It believes the theoretical density gain of 4F² will be offset by extra process steps and yield loss. Giving up 4F² is a calculated decision based on its supply chain advantages: maximizing returns from proven scaling and unlocking long-term performance through 3D stacking.

      CXMT’s 4F² design is developed under a different industrial backdrop. Its core innovation is the proprietary VSG (Vertical Surrounded Gate) transistor, which cuts planar cell area by one third and lifts theoretical density by about 50%, reducing per-bit cost under the same process node. This “same process condition” is the core value of this architecture. Restrictions on access to advanced EUV lithography limit the conventional scaling path. Under such circumstances, architectural innovation becomes a critical way to narrow the technology gap. If 4F² + VSG achieves stable mass production, it offers a route to improve cost competitiveness without EUV equipment. This is why the announcement strongly impacted market consensus that advanced DRAM cannot catch up without EUV.

      The timing further amplifies its influence. Samsung targets 4F² DRAM mass production in 2028, while CXMT could launch related products by late 2026, creating an approximate two-year window in architecture development. Coupled with CXMT’s growing global market share, investors worry the long-standing supply discipline and price stability led by international giants may face disruption from low-cost mass production.

      Nevertheless, technical progress does not eliminate the overall technology gap. Between design verification and stable mass production lie three tough barriers: yield stability, manufacturing cost, and long-term reliability certification from major server customers. Products launching at the end of 2026 are only the starting point; mass yield, unit cost and qualification by tier-one server clients will determine the real viability of this route.

      Most analysts note that CXMT still lags global leaders in cutting-edge memory technology. The sharp market reaction mainly reflects revised expectations of incumbents’ technical moat, rather than an immediate reversal of the industry landscape.

      Geopolitics adds another layer of complexity. Reports indicate Apple has begun sampling CXMT DRAM and discussed relevant usage policies. Financial institutions forecast that even if these chips are restricted from the US market, shipments to Europe and other regional datacenters will still reshape global DRAM supply and demand.

      Memory competition goes far beyond specification comparison, reshaping the whole semiconductor supply chain. The split strategy between Micron and CXMT represents two optimized solutions under different external constraints: vendors with full access to advanced manufacturing tools stick to steady process scaling, while others pursue architectural disruption to create breakthroughs. There is no universal correct roadmap. Future mass-production data and downstream adoption will continue to guide the industry’s direction.

Reference: Public industry reports. This is our independent market analysis, not a reprint.