SK hynix begins mass production of world's first 321-layered NAND chips

SK hynix's 321-layered NAND flash memory chip [SK HYNIX]

SK hynix will begin mass production of the world's first 321-layered NAND flash memory chips in the first half of 2025, continuing the lead in the NAND market with advanced technology in the face of the booming AI market.

The Korean memory chipmaker unveiled the sample of the 321-layered NAND flash chip at the Flash Memory Summit 2023 that kicked off its three-day run in Santa Clara, California, on Tuesday.

This is the first time any chipmaker has revealed a specific development timeline of a NAND with more than 300 layers.

The sample SK hynix showed at the summit was a 321-layered TLC 4D NAND flash with a one-terabyte capacity.

TLC, or triple-level cells, refers to a type of NAND flash memory that stores three bits of data per cell, meaning higher data density and lower cost than single-level cell NANDs.

"The company will fortify its leadership in NAND technology with the development of fifth generation 321-layered 4D NAND," Choi Jung-dal, SK hynix's head of NAND development, said at the summit in his keynote speech.

"We are going to showcase high-performance, high-capacity NAND to the market in response to the AI era."

The 321-layered NAND has upgraded its productivity by 59 percent from that of the 238-layered 512-gigabyte NAND, which SK hynix began mass production for the first time in the world in May. It means that the chipmaker can make that many more chips from the same size of a wafer.

SK hynix is outperforming its rivals in the number of layers. Samsung Electronics is currently mass-producing 236-layered NAND and Micron 232-layered.

The NAND market, however, is yet to recover from a glut. Samsung Electronics and SK hynix said in their respective conference calls last month they would further cut production of NAND in the second half.

SK hynix stands in the fourth spot in the global NAND flash memory chip market with a 16.8 percent share, according to market tracker Omdia. Samsung tops the list, followed by Kioxia and Western Digital.

Samsung Electronics unveiled a line of storage solutions and technology that can be applied to servers, PCs and automotives.

It showcased its newest solid-state drive (SSD), named PM9D3a, based on the eighth generation of its vertical NAND that supports eight channels and PCIe 5.0 standards. It has upgraded power efficiency by 60 percent compared to the previous generation and has achieved 25 million hours of MTBF (mean time between failure) which is a 25 percent improvement compared to the prior version.

It also unveiled the PM1743 SSD with upgraded power efficiency, which is used in applications like generative AI which requires large storage space.

"Customer experience will continue to come first [for Samsung Electronics]," said Song Yong-ho, executive vice president of Samsung's Memory Solution Product & Development.

"We will continue to cooperate with customers to provide the most optimized memory solutions."

BY JIN EUN-SOO [jin.eunsoo@joongang.co.kr]