SEOUL, South Korea – SK hynix has announced that it has begun mass production of the world's tallest 321-layer 4D NAND flash memory, marking a significant milestone in the industry. The company plans to start supplying the new chips to customers in the first half of next year.

NAND flash memory is a type of non-volatile memory that retains data even when power is off. The key to increasing storage capacity is through a process called stacking, where multiple layers of cells are vertically stacked. SK hynix has been at the forefront of this technology, having previously introduced the industry's tallest 238-layer NAND in June 2022.

The new 321-layer NAND offers several advantages over its predecessor. It provides a 12% improvement in data transfer speed and a 13% improvement in read performance. Additionally, it consumes 10% less power during data reads. SK hynix plans to leverage this new product to expand its market presence in the AI-focused low-power, high-performance market.

To achieve this breakthrough, SK hynix introduced a new production process called "3-plug." This process involves creating three vertical holes in the stacked layers and then electrically connecting them through an optimized subsequent process. This method helps to overcome the limitations of stacking more layers.

"With both HBM (High Bandwidth Memory) and NAND, we are poised to become a 'full-stack AI memory provider' with a complete portfolio of ultra-high-performance memory," said Choi Jeong-dal, vice president of NAND development at SK hynix.