YMTC Xtacking4.0: Breaking New Ground in 3D NAND Technology

YMTC continues to push the boundaries of 3D NAND technology with the introduction of its Xtacking4.0 (Gen5) process. Building on the foundation of its previous generations, including Xtacking2.0 (128L, Gen3) and Xtacking3.0 (232L, Gen4), the latest iteration integrates a range of innovations aimed at enhancing storage density, speed, and energy efficiency. With TechInsights' comprehensive analysis of YMTC’s 3D NAND evolution from Gen1 to Gen5, it is clear that Xtacking4.0 brings notable advancements in process and design. In this blog, we’ll explore the technical breakthroughs that differentiate Xtacking4.0 from its predecessors and what they mean for the future of YMTC’s NAND technology.

Key upgrades in Xtacking4.0 include:

1. Centered X-DEC die design: This architectural enhancement improves read/write performance by reducing wordline (WL) capacitance and RC load, cutting WL settling time and current demands.
2. Backside Source Connect (BSSC): First used in Xtacking3.0, BSSC helps streamline vertical connections, now applied to the 160-layer TLC chip for enhanced performance.
3. Vertical channel (VC) design: The 20-hole VC design, shared with KIOXIA’s BiCS8 218L, eliminates dummy holes, optimizing the 155 nm pitch for better cell density and efficiency.
4. Higher bit density and reduced die size: With a die size of 40.44 mm² and a density of 12.66 Gb/mm² for the 512 Gb chip, Xtacking4.0 offers increased storage capacity and performance within a smaller footprint.
5. Hybrid bonding maturity: This technology, crucial to YMTC’s process, is now more refined and is the backbone of YMTC’s high-density, vertically connected 3D NAND chips.

These improvements reflect YMTC's efforts to mitigate the challenges of U.S. sanctions by advancing its technology, boosting yields, and preparing for further product diversification.