In a rather unexpected turn of events, Western Digital (WD) has introduced the industry's first 2Tb 3D QLC NAND device, which could potentially reshape the high-capacity solid-state drives market. The device uses the proven 218-layer BiCS8 production node and is so tiny it can fit on a fingertip.
"I am really excited to share with you a preview of the BiCS8 2Tb 3D QLC die," said Robert Soderbery, Executive Vice President and General Manager of Western Digital's Flash Business. "We have designed this die to meet the datacenter and AI storage needs. We are going to be shortly announce this product, but I want to share it with you today. This happens to be world's highest capacity memory die."
A 2Tb (256GB) 3D QLC NAND die is indeed a huge achievement, as the 'base' product that Western Digital introduced on its 218-layer BiCS8 production technology is a 1Tb 3D TLC device. At this point, we have no idea about the exact architecture of the 2Tb IC, such as the speed of its interface (it is probably fast), or the number of planes, or its latency. But given the fact that the company positions the device for data centers in general and AI storage needs in particular, one can make some assumptions about its performance.
Now, a 256GB 3D QLC NAND device allows manufacturers to build a 1TB SSD using just four memory ICs and a 2TB drive using eight devices, which greatly lowers their costs. Assuming that Western Digital (and its manufacturing partner Kioxia) can produce these 2Tb 3D QLC NAND ICs in high volume and with decent yields, the new device can redefine the cost of high-capacity solid-state drives.
One of the mysteries about the new 2Tb QLC NAND is how it is actually made. While Western Digital points to its 218-layer BiCS8 node, it also highlights the extremely tiny size of the die, so the company may have stacked two 218-layer NAND arrays on top of each other to achieve the extremely small die size, but we are speculating at this point.
"We typically show you a wafer, but I felt like the view of a wafer does not quite convey what we have achieved," said Sodebery. "So, if you allow me for a quick second, I want to show you the die. I have one here. Please zoom in [on] what I am holding on my finger here. This is the size of the die, much smaller than my fingertip."
Western Digital plans to formally announce its 2Tb 3D QLC NAND device in the near-future, when it will disclose its full specifications.
