YMTC's Phase 3 fab in Wuhan, slated to begin mass production in the second half of 2026, is built with more than 50% of its equipment, materials, and tools sourced from Chinese domestic suppliers. That is the headline number. Phase 1 and Phase 2 were largely built around Western fabrication equipment before 2022 U.S. restrictions cut off access to ASML, Applied Materials, and others. Phase 3 is the first real test of whether China's homegrown fab equipment ecosystem has matured enough to produce competitive NAND at volume.
The architecture news is arguably more interesting. YMTC's Xtacking 4.0 runs at 270 layers, behind SK Hynix's 4D NAND at 321 layers and Samsung's 9th-gen V-NAND at 286 layers -- but the gap has narrowed substantially. The Xtacking approach separates logic and memory array onto two dies, which improves array efficiency and bit density compared to conventional monolithic 3D NAND. YMTC held 11.8% of the $52 billion global NAND market in 2025. With three new fabs targeting 100,000 wafers per month each, they are targeting 20% of global supply.
The sanctions-bypass angle is real but should be read carefully. Domestic equipment suppliers like AMEC have filled specific niches -- etching, MOCVD -- but whether they can cover the full process flow for leading-edge NAND at yield is unproven at scale. Phase 3 is the proof of concept. If YMTC hits its 2027 yield targets on domestically equipped lines, the efficacy of U.S. export controls on advanced memory looks very different.
For hardware engineers tracking memory availability: YMTC's primary market is China's domestic OEM ecosystem -- Acer, Adata, Lexar, and others benefit from government subsidies for using local chips. That keeps Phase 3 output largely captive in the near term. But the longer arc here is a Chinese memory industry that is systematically reducing its dependency on Western tooling, at 270 layers and climbing.