China’s YMTC takes lead in 3D-NAND memory
YMTC has progressed rapidly. The company was founded on July 16, 2016 by China’s Tsinghua Unigroup, which owns 51 percent of the company, with help from the national investment fund and a number of smaller municipal funds from the province of Hubei.
The company has now introduced a 128-Layer 3D-NAND non-volatile memory – the X2-6070 – with four-bits per cell (QLC) and a total capacity of 1.33Tbits. In July 2019 Samsung announced a 1xx-layer device (widely supposed to be 128 layers or near). However, that chip only supported 3-bits per cell and had a total memory capacity of 256Gbits.
YMTC now claims: “As the first QLC-based 128-layer 3D NAND, X2-6070 has achieved the highest bit density, highest I/O speed and highest capacity so far among all released flash memory parts in the industry.” The company adds the caveat that it is comparing against 3D-NAND chips that can be bought in the market.
YMTC has also introduced a 512Gbit, 3bit per cell 128-layer device – the X2-9060 – to meet a more diverse range of applications.
Competitors such as SK Hynix, Micron and Kioxia are generally at 96-layers. Kioxia and Western Digital announced the development of a 512Gbit, 3bit per cell 112-layer device in January 2020, but also said that volume production would not happen until 2H20.
YMTC has not said when it will be in volume production with the X2-6070 and the X2-9060.
YMTC calls its approach to vertical stacking of NAND flash Xtacking. In its 128-layer line of products, Xtacking has been upgraded to version 2.0, which has enabled a read/write performance of 1.6Gbps on both X2-6070 and X2-9060 by using 1.2V Vcc.
“This QLC product [X2-6070] will first be applied to consumer-grade solid-state drives and will eventually be extended into enterprise-class servers and data centers in order to meet the diverse data storage needs of the 5G and AI era,” said Grace Gong, senior vice president of sales and marketing at YMTC, in a statement.
Gregory Wong, principal analyst at Forward Insights, said QLC was a necessary development to save cost and that the characteristics of QLC made it suitable for high-capacity storage media.
Related links and articles:
China catching up in 3D-NAND flash race
China’s YMTC takes 3D-NAND to 64 layers
‘Xtacking’ approach offers faster 3D-NAND, claims Yangtze
Samsung ramps production of 96-layer 3D-NAND flash
Toshiba starts sampling 96-layer, quad bit 3D-NAND