In a nutshell: Western Digital plans to begin mass production of 162-layer BiCS6 3D NAND memory, which is likely to be used in PCIe 5 SSDs by the end of this year. The company is also working on NAND with more than 200 layers designed for storage in data centers, PLCs, and ways to connect multiple 3D NAND wafers to increase the number of layers.
Western Digital, along with partner Kioxia, have just presented us with their NAND roadmap for the next few years. The company plans to introduce 6th generation BiCS soon, which will have 162 layers in TLC and QLC configurations.
While this may not seem all that impressive, given that competitors such as Micron have had 176-layer NAND for some time now, WD says they will reduce the memory cell size using the new material, resulting in smaller die sizes.
The company hopes this will allow them to build cheaper storage devices that are as good as they are in performance. Mass production of BiCS6 3D NAND is scheduled to start in late 2022, and WD plans to use these chips in products ranging from cheap USB flash drives to PCIe 5.0 SSDs.
WD also talked about their upcoming BiCS+ memory with over 200 layers, due by 2024. It will have 55% more bits per platter, 60% faster bit rate and 15% faster write speed compared to BiCS6.
It’s worth noting that BiCS+ is only intended for use in data center SSDs, as the company plans to offer another class of 2xx-layer NAND for consumer storage, dubbed BiCS-Y.
Western Digital also said that they are working on several technologies to increase density and capacity, including PLC, and that they plan to build NAND with over 500 layers over the next decade.