Samsung and SK Hynix Shares Decline Following CXMT Memory Cell Update

Shares of Samsung and SK Hynix fell following an Investing.com report that detailed advancements by Chinese competitor ChangXin Memory Technologies (CXMT) in high-density DRAM design. Samsung shares declined 3.6% to 252,500 won, and SK Hynix stock dropped 3.4% to 1,624,000 won after the announcement.

The market reaction centers on CXMT’s progress in developing a 4F² memory-cell structure. This design aims to increase storage density compared to the current 6F² configuration. By shrinking the footprint of each cell, manufacturers can fit more memory onto the same silicon wafer to lower the cost-per-bit.

"The company plans to introduce a new generation of DDR5 RDIMMs based on the 4F² structure by the end of 2026," said CXMT President Cao Kanyu in a statement regarding the development.

The Shift to 4F² Architecture

The transition from 6F² to 4F² is an engineering challenge in the memory semiconductor industry. The 6F² structure has served as the baseline for DRAM production for years, and the 4F² design is considered the next step for scaling capacity in high-performance computing and data centers.

South Korean companies are preparing for this technological change. SK Hynix unveiled its own 4F² development roadmap in 2025, and Samsung has targeted mass production of sub-10-nanometre DRAM using the 4F² design by 2028. The entry of a Chinese competitor into this development cycle suggests a narrowing of the technological gap that has historically favored South Korean firms.

Competition in DRAM

The market reaction shows investor sensitivity to the competitive positioning of DRAM manufacturers. As global demand for high-bandwidth memory rises, the ability to transition to denser cell structures is necessary for maintaining margins and market share.

For Samsung and SK Hynix, the challenge involves balancing the capital costs of these R&D efforts while contending with more manufacturers capable of producing advanced memory components. The timeline provided by CXMT suggests that competitive pressure in the DRAM sector may increase as the industry approaches the 2026 to 2028 window for mass-market adoption of 4F²-based hardware.