SK hynix unveils world’s first 321-layer QLC NAND, targets 1H26 commercial launch

SK hynix announced that it has developed a 321-layer 2Tb QLC NAND flash and has already begun mass production. This is the world’s first QLC device to exceed 300 layers, setting a new milestone in NAND density. The product is scheduled for release in the first half of 2026, following completion of global customer validation.

The 321-layer QLC NAND delivers higher capacity and improved performance compared with earlier QLC products. The new 2Tb device provides twice the capacity of existing solutions.

To address potential performance challenges in high-capacity NAND, the company increased the number of planes—independent operating units within a chip—from four to six. This change enables greater parallel processing and significantly boosts simultaneous read performance.

For this product, data transfer speed has doubled, write performance has improved by up to 56%, and read performance by 18%. The write power efficiency has risen by more than 23%, strengthening its competitiveness in AI data centers where energy efficiency is critical.

SK hynix plans to apply its 321-layer NAND first to PC SSDs, before expanding to enterprise SSDs (eSSD) for data centers and UFS solutions for smartphones.

Notably, SK hynix is also targeting the ultra-high-capacity eSSD market for AI servers by leveraging its proprietary 32DP3 technology, which doubles integration density through the simultaneous stacking of 32 NAND dies in a single package.

Source: TrendForce, Taiwan.