[Edaily Reporter JAEMIN SONG ] As U.S.-based Micron has abandoned the commercialization of the “4F² (4F Square)” cell structure—long considered a core technology for next-generation DRAM—the technology development strategies of the world’s top three memory semiconductor companies are diverging. While SamsungElectronics and SK hynix are continuing to develop 4F², Micron has decided to focus on refining its existing processes and on 3D DRAM. As DRAM miniaturization nears its physical limits, the future competitive landscape is expected to shift depending on the technology choices made.

According to the semiconductor industry and foreign media reports on the 26th, Micron announced its policy of not adopting 4F² while unveiling its memory technology roadmap for the next 10 years during a technology webinar on the 21st (local time). Scott Devore, Micron’s president and chief technology and product officer (CTPO), explained that although the company had researched the technology for over 20 years, it decided not to pursue commercialization due to process complexity, rising costs, and the fundamental limits of miniaturization.

4F² is a technology that theoretically reduces the area occupied by a single DRAM cell by approximately 33% compared to the existing 6F². It has been cited as a key technology for next-generation DRAM scaling, as reducing cell area can increase integration density. However, Micron determined that reducing cell area does not directly translate to improved integration density. DRAM integration density is determined not only by the transistor structure but also by the spacing of the capacitors that store charge; even with the adoption of 4F², manufacturing costs and process complexity could increase.

During the Q&A session of a webinar, Devore, CTPO, assessed the claim that 4F² offers practical advantages over 6F² as “somewhat of a myth.” He explained that while 4F² can be implemented in older processes, it increases costs and complexity, and that as processes become more advanced, they face physical scaling limits.

Micron, on the other hand, plans to focus on wafer bonding and the development of 3D DRAM while improving its existing 6F² architecture. Following the 1-gamma (1γ) process currently in mass production, the company plans to begin mass production of the next-generation 1-delta (1δ) DRAM in the second half of 2027. For the subsequent 1-epsilon (1ε) process, the company intends to increase integration density by introducing bonding technology that combines different wafers. In the long term, the plan is to transition to 3D DRAM, which stacks memory cells vertically, though the timing of commercialization will be determined based on factors such as manufacturing costs and performance.

Meanwhile, SamsungElectronics and SK hynix are continuing to develop 4F² technology. SamsungElectronics is researching technology to reduce cell area by utilizing vertical channel transistors (VCTs), while SK hynix is also pursuing the development of next-generation cell structures based on vertical gates (VG). Although both companies are researching 3D DRAM for the long term, they differ from Micron in that they are maintaining 4F² as a candidate for next-generation technology.

The pursuit by Chinese companies is another variable. China’s Changxin Memory Technology (CXMT) has announced plans to unveil 4F²-based DDR5 memory modules for servers by the end of this year. However, specific product performance, mass production yield, and manufacturing cost competitiveness have yet to be confirmed.

Consequently, competition in next-generation DRAM is expected to evolve beyond simple circuit miniaturization into a contest over the integration density improvements offered by each technology and the economic viability of mass production. In particular, the key issue will be determining which approach—reducing cell area through 4F², improving existing processes, or 3D stacking—will secure higher integration density and lower production costs.

SamsungElectronics recently publicly confirmed its commitment to continuing the development of 4F² technology. Song Jae-hyuk, President and Chief Technology Officer (CTO) of SamsungElectronics’ Device Solutions (DS) Division, answered “Yes” when asked about the development of 4F² technology at the Semiconductor Expo (SEDEX 2026) on the 14th. Regarding the specific progress of the development, he remained tight-lipped, saying only, “We’re working hard on it.”