SK hynix Starts 321-Layer QLC NAND Flash Production

Seoul, South Korea - SK hynix Inc said on Monday it has started mass production of 321-layer QLC NAND flash memory.

The company stated that this represents the first implementation of more than 300 layers utilizing quad-level cell technology.

The South Korean memory chipmaker completed development of its 2-terabit QLC NAND product.

The commercial release is scheduled for the first half of 2026, following customer validation, the company said.

SK hynix said the 2Tb device has double the capacity of existing solutions. The company increased the number of planes from four to six. Planes are independent operation units within a chip.

According to SK hynix, data transfer speed has doubled compared to previous QLC products.

Write performance improved by 56 percent, and read performance improved by 18 percent. Write power efficiency increased by more than 23 percent.

The company said it will apply 321-layer NAND first to PC solid-state drives, then expand to enterprise SSDs for data centers and universal flash storage for smartphones.

SK hynix said it will use its 32DP technology, which stacks 32 NAND dies in a single package, to achieve twice the integration density for enterprise SSDs for AI servers.

Jeong Woopyo, head of NAND development at SK hynix, stated that the company has expanded its high-capacity product portfolio and enhanced cost competitiveness with the commencement of mass production.

Jeong said SK hynix aims to expand as a full-stack AI memory provider, citing growth in AI demand and high-performance requirements in the data center market.