Micron drops 4F² DRAM, bets on 6F² and 3D roadmap
Micron will start mass production of 1δ DRAM in Boise in the second half of 2027 and add wafer bonding in the 1ε node.
Micron Technology has officially abandoned plans to adopt the 4F² DRAM cell structure and will instead extend its existing 6F² design across future nodes, the company said at a technology webinar held on October 21 local time, according to etnews.com.
Micron's presentation materials state that the company has researched 4F² for more than 20 years but has found no viable scaling path. Scott DeBoer, Micron's president and chief technology and product officer, said there are fundamental problems with 4F² scaling and that its density advantage over 6F² is "somewhat mythical," the report said.
Roadmap through 2027 and beyond
Under the multi-generation roadmap presented at the webinar, Micron will begin mass production of next-generation 1δ DRAM in Boise, Idaho, in the second half of 2027. The 6F²-based successor node, 1ε, will introduce wafer bonding technology.
Micron also placed 3D DRAM, split into 3D1 and 3D2 stages, officially between the 1ζ and 1η nodes. Separately, the company unveiled Vertical HBM, which stacks memory directly on top of the processor and connects it using hybrid bonding.
Rivals have taken a different route: Samsung Electronics and SK Hynix have been researching VCT-based 4F² structures to overcome the physical limits of sub-10nm (0a/0b) processes. In a separate development, CXMT recently announced plans to commercialize server DRAM using a 4F² structure, which shook global memory semiconductor stocks and sent Korean companies' shares falling sharply.
Quick answers
What did Micron announce about 4F² DRAM?
Micron said it has abandoned adopting the 4F² DRAM cell structure and will extend its existing 6F² structure instead, citing no viable scaling path after more than 20 years of research.
When will Micron mass-produce 1δ DRAM?
Micron plans to begin mass production of next-generation 1δ DRAM in Boise, Idaho, in the second half of 2027.
What is Micron's Vertical HBM?
It is memory stacked directly on top of the processor and bonded using hybrid bonding, which Micron unveiled at its October 21 technology webinar.