SK Hynix starts making 128-layer NAND flash
The development comes eight months after the company developed the previous generation, the 96-layer NAND flash.
Shipping of the 128-layer NAND flash will begin in coming months.
The Korean chipmaker said its latest chip offers the highest density for a triple-level cell (TLC) NAND flash. It stores 1 terabit of data in total. It is the first time a TLC NAND flash that stores 1 terabit data has been commercialized, according to SK Hynix.
On each cell of a TLC NAND chip, 3 bits of data is stored. Depending on the amount of data stored in each NAND cell, the chips can be categorized into single-level cell, multi-level cell, triple-level cell and quadruple-level cell.
Single-level means each cell stores 1 bit of data while quad-level means each cell stores 4 bits of data.
An SK Hynix spokesperson said TLC products account for 85 percent of the NAND flash market.
The company said that use of its 1 terabit NAND flash will cut the number of NAND chips necessary for a smartphone with 1 terabyte internal storage, currently the largest capacity for a phone, to half.
SK Hynix calls the new chip a 128-layer 1 terabit TLC 4D NAND flash. It started branding its vertically stacking technology 4D last October to differentiate its technology from 3D NAND products.
While multiple layers of memory cells are stacked vertically in three-dimensional structure as well, SK Hynix moved peripheral logic circuitry, which make major decisions for cells, to underneath flash cells to make chips smaller and efficient.
BY KIM JEE-HEE [email@example.com]