Samsung Electronics on Wednesday announced that it has begun mass producing the industry's first 3-bit, multi-level-cell (MLC) three-dimensional (3D) NAND flash memory for use in solid state drives (SSDs) for PCs and other devices.
The 3D or V-NAND (vertical NAND), as Samsung calls it, is a second-generation chip, which utilizes 32 vertically stacked cell layers per NAND memory chip. Each chip provides 128 gigabits (Gb) of memory storage. The previous generation chip, announced in August 2013, used two bits per cell.
The use of 3-bit-per-cell V-NAND sharply raises the efficiency of memory production, Samsung said in a statement. Compared to its 3-bit planar (or single layer) NAND flash, the new 3-bit V-NAND has more than doubled wafer productivity in Samsung's factory, the company said.
One of the most important achievements of the Samsung V-NAND is that the proprietary vertical interconnect process technology can stack as many as 32 cell layers vertically, using special etching technology that connects the layers electronically by punching holes from the highest layer to the bottom.
While stacking layers of NAND sounds like it would produce thicker chips, Samsung said the increase "is negligible compared to the most up-to-date planar NAND flash memory chip" -- less than a few microns in height.
Unlike planar NAND, Samsung's V-NAND uses cell structure based on 3D Charge Trap Flash (CTF) technology and vertical interconnect process technology to link the cell array. By applying the latter technologies, Samsung's 3D V-NAND can provide over twice the scaling of 20nm-class planar NAND flash.
Samsung introduced its first generation V-NAND (24 layer cells) last year, and rolled out its second-generation V-NAND (32-layer) cell array structure in May. The launch of the 32-layer, 3-bit V-NAND, means Samsung is speeding up the evolution of V-NAND production technology.
"With the addition of a whole new line of high-density SSDs that is both performance- and value-driven, we believe the 3-bit V-NAND will accelerate the transition of data storage devices from hard disk drives to SSDs," Jaesoo Han, senior vice president of Samsung Electronic's marketing and sales, said in a statement.