SK hynix Launches Mass Production of 321-Layer QLC NAND Flash for AI and High-Capacity Storage

SK hynix  has begun mass production of its 321-layer 2Tb Quad-Level Cell (QLC) NAND flash, the first NAND product to exceed 300 layers using QLC technology. The company completed development of this 2Tb device, which doubles the capacity of existing solutions, and plans to launch it commercially in the first half of 2026 after global customer validation.

To address performance challenges in large-capacity NAND, SK hynix increased the number of independent operation units, or planes, from four to six, enabling greater parallel processing. This results in a data transfer speed increase of up to 100%, write performance improvement of 56%, read performance enhancement of 18%, and a 23% increase in write power efficiency compared to previous QLC products.

The 321-layer QLC NAND will first be applied to PC SSDs, with plans to expand to enterprise SSDs (eSSDs) for data centers and Universal Flash Storage (UFS) for smartphones. Using its 32DP technology, which stacks 32 NAND dies in a single package, SK hynix aims to target the ultra-high-capacity eSSD market for AI servers. Jeong Woopyo, Head of NAND Development at SK hynix, stated that the mass production strengthens the company’s high-capacity product portfolio to mee...