Western Digital has started sampling its 96-layer 3D NAND chips featuring QLC architecture that stores four bits per cell. The chip happens to be the world’s highest-capacity 3D NAND device. The company expects to commence volume shipments of this memory chip already this calendar year.
Western Digital’s 96-layer BICS4 3D QLC NAND chip can store up to 1.33 Tb of raw data, or around 166 GB. The IC will be initially used for consumer products Western Digital sells under the SanDisk brand, so think of memory cards (e.g., high-capacity SD and microSD products), USB drives, and some other devices. The manufacturer expects its 3D QLD NAND memory to be used in a variety of applications, including retail, mobile, embedded, client, and enterprise, but does not elaborate on timing at this point.
The 1.33-Tb BICS4 IC is Western Digital’s second-gen 3D QLC NAND device. Last year the company announced its BICS3 64-layer 3D QLC chips featuring a 768 Gb capacity, but it is unclear whether they have ever been used for commercial products. Meanwhile, it is clear that the device was used to learn about 3D QLC behavior in general (i.e., endurance, read errors, retention, etc.)
Western Digital and its manufacturing partner Toshiba started volume production of 96-layer 3D NAND earlier this year. Western Digital confirmed in late May that it had begun volume shipments of its BiCS4 memory to its retail customers, which most probably means that the new 96-layer 3D NAND ICs were used for select SanDisk-branded products. The first BiCS4 products that Western Digital announced were 256 Gb 3D TLC ICs, so it is highly likely that they have been in mass production for some time now.
As it appears, yields of 96-layer 3D NAND have been good enoug,h and things that the company has learned with BiCS3 QLC were substantial, so Western Digital moved right to its top-of-the-range capacity of 1.33 Tb per chip. What is noteworthy is that officially the BiCS4 range was to include both TLC and QLC ICs with capacities ranging from 256 Gb to 1 Tb, so the 1.33 Tb IC is a surprising addition to the lineup which signals Western Digital’s confidence of its technology.