Kioxia aims to launch 1,000-layer NAND flash memory by 2031 and restructure storage-class memory business

On April 7, according to Nikkei xTECH, Kioxia CTO Hidefumi Miyajima stated at the 71st Spring Academic Lecture Meeting of the Japan Society of Applied Physics that the company aims to launch 1,000-layer 3D NAND flash memory in 2030-2031 and has reorganized its storage-class memory (SCM) business.

Kioxia and Western Digital have worked together to develop NAND flash memory technology, and the most advanced product currently offered by the partnership is the 218-layer stacked BICS8 3D flash memory. BICS8 flash memory can achieve an I/O rate of 3200MT/s.

Samsung, another major NAND company, made a similar point at its Technology Day in 2022, when it predicted the realization of 1,000+ layer stacked 3D NAND flash memory by 2030.

Increasing the number of stacked layers is the main way to increase the capacity of a single 3D NAND flash memory particle. However, in the process of increasing the number of layers, the difficulty of etching vertical channels in flash memory particles gradually increases as the aspect ratio increases.

In addition to the high difficulty and low yield, high aspect ratio etching is also a time-consuming and costly process: currently each etching process takes about 1 hour, and if NAND manufacturers want to increase production capacity, they must purchase more etching machines.

Therefore, Kioxia used a dual-stack process in BICS8 to separately implement vertical channel etching of the two NAND stacks.

Although this move adds extra trouble to the channel between the two stacks, it reduces the difficulty overall. In the future, thousand-layer stacked NAND flash memory is expected to include more NAND stacks.

In addition, Hidefumi Miyajima also stated that compared with competitors that operate both NAND and DRAM, Kioxia is at a competitive disadvantage in terms of business richness, so it is necessary to cultivate new storage product businesses such as storage-class memory (SCM).

The CTO said that amid the AI ​​boom, the performance gap between DRAM and NAND is widening, and SCM can fill this gap.

Kioxia reorganized the previous "Memory Technology Research Laboratory" into the "Advanced Technology Research Laboratory" on April 1. Its SCM research will focus on new memory such as MRAM, FeRAM, and ReRAM, which are expected to be shipped within 2 to 3 years.

According to previous reports, Kioxia previously focused on XL-FLASH flash memory solutions in the SCM field. In 2022, the company launched the second-generation XL-FLASH that supports MLC mode.