South Korean chipmaker SK hynix announced the start of mass production of the world’s first 321-layer QLC NAND flash memory. Moreover, the new product breaks through technological limits and sets a new benchmark in semiconductor development. Consequently, the company has strengthened its competitiveness as demand for advanced memory rises in the AI era.
The company emphasized that the new chip represents the highest density ever achieved in NAND technology. Furthermore, by using a quadruple-level cell design, engineers managed to store four bits per cell. As a result, the chip doubled storage capacity to 2 terabits. Therefore, this achievement reinforces the leadership of the South Korean semiconductor industry.
The chip mainly targets data-intensive industries, especially AI data centers. In addition, these facilities need memory that balances speed with energy efficiency. SK hynix confirmed that the product will undergo global validation before launch. Ultimately, with AI workloads expanding, the company expects wide adoption.
Performance upgrades define this innovation. Specifically, engineers increased the number of planes in the chip from four to six. Consequently, the chip handles more parallel operations, which doubled data transfer speeds compared to earlier products. Writing speed improved by 56 percent, while reading rose by 18 percent. Meanwhile, power efficiency advanced by 23 percent, making the chip attractive for large-scale AI use.
The South Korean semiconductor leader plans to roll out the 321-layer NAND in stages. Initially, it will power solid-state drives for PCs. Later, the company will expand to smartphones and large-scale data centers. Moreover, SK hynix will apply its packaging technology to stack 32 chips together. This method doubles integration density and supports enterprise SSDs designed for AI servers.
Executives highlighted that the launch strengthens both portfolio depth and cost competitiveness. In addition, Jeong Woo-pyo, head of NAND development, confirmed the company’s goal to become a full-stack AI memory supplier. Therefore, the new chip marks a leap forward for South Korean semiconductor innovation and global AI growth.

