China's Yangtze Memory Technology (YMTC) has started delivering samples of its 64-layer 3D NAND chip with volume production likely to kick off in the third quarter of 2019, according to sources familiar with the matter. The company also plans to move directly to the 128-layer generation with volume production scheduled for 2020.

YMTC has no plans to provide 96-layer 3D NAND chips as the company intends to skip the generation and jump directly to 128 layers, the sources noted.

YMTC's in-house developed Xtacking™ architecture is already adopted in the company's 64-layer 3D NAND engineering samples. Xtacking™ enables YMTC's 64-layer 3D NAND to be competitive with the available 96-layer 3D NAND solutions, the sources continued.

YMTC CEO Simon Yang was quoted in previous reports that the company is set to enter volume production of 64-layer 3D NAND flash memory in the fourth quarter of 2019. Yang added YMTC's 32-layer 3D NAND process technology is pretty mature and has been involved in production for small-volume orders.

The roll-out of 64-layer 3D NAND process technology will enable YMTC's product gross margin to turn positive from negative, said Yang, adding that the company expects its monthly production capacity to hit 100,000 wafers after moving 64-layer 3D NAND technology to volume production.