SK hynix said Thursday it has started mass production of the industry's first triple-level cell-based 321-layer NAND flash memory chips.

NAND flash memory is a non-volatile memory storage medium widely used in memory cards, USB drives, solid-state drives (SSDs), and smartphones for general storage and data transfer. It stacks memory cells vertically and is categorized into single-, multi-, triple-, and quadruple-level cells.

SK hynix announced that it has become the world's first supplier of NAND flash memory with more than 300 layers, building on the success of its 238-layer product, which entered mass production in June 2023.

The company plans to begin delivering the 321-layer products to customers in the first half of next year.

SK hynix said the latest development brings it a step closer to becoming the leader of the AI storage market, represented by SSDs for AI data centers and on-device AI.