What is V-NAND and how is it different to existing technology?
Samsung's three-dimensional V-NAND (Vertical NAND) flash memory is fabricated using an innovative vertical interconnect process technology to link the 24-layer 3D cell array based on Samsung's 3D Charge Trap Flash (CTF) structure.
An industry first, it represents a breakthrough in overcoming the density limit currently facing the planar NAND architecture and floating gates used in conventional flash memory, as well as yielding speed and endurance improvements.
Key characteristics and benefits of V-NAND
For the past 40 years, conventional flash memory has been based on planar structures that make use of floating gates. However, with current manufacturing process technology in the 10 â 20 nm range, further improvements in chip density are limited by cell-to-cell interference, necessitating trade-off in the reliability of NAND flash products in addition to added development time and costs.
In Samsung's CTF-based NAND flash architecture, first developed in 2006, an electric charge is temporarily placed in a holding chamber of a non-conductive layer of flash composed of silicon nitride (SiN), instead of using a floating gate, to mitigate interference between neighbouring cells. By making this CTF layer three-dimensional, the reliability and processing speed of our V-NAND has been significantly improved. Furthermore, by applying both of these technologies, Samsung's 3D V-NAND is able to provide over twice the scaling of 20 nm-class planar NAND flash.
In addition, our new V-NAND exhibits between two to ten times the reliability (endurance) and writes data (tPROG, program time) at least twice as fast as multi-level-cell (MLC) type planar NAND flash memory, while consuming half the power.
Samsung's new V-NAND offers a 128 gigabit (Gb) density in a single chip.
Production of 24-layer 128Gb V-NAND chips started as of this month (August) in Hwaseong, Korea. Samsung has core technologies to develop more advanced high-density devices and is seeking to develop manufacturing technologies for stacking more than 24 cell layers in the future.
Applications of V-NAND
The new 3D V-NAND will be used for a wide range of consumer electronics and enterprise applications, including embedded NAND storage and solid state drives (SSDs).
Based on its superior benefits, V-NAND can be applied to NAND flash devices that require high-density and high-performance.
As our new V-NAND offers a minimum of double and up to ten times the reliability of planar MLC NAND, we expect to provide an extensive range of products to satisfy global customer and market needs.
Samsung has set the foundation for more advanced products including 512 gigabit (Gb) and one terabit (Tb) NAND flash memory, which we expect to develop within the next few years.