Samsung moves nearer to its 1,000‑layer NAND ambition by bonding two 450‑layer V‑NAND dies into a single 900‑layer stack. The process relies on Cell Multi‑Bonding (CMB), a hybrid‑bonding technique that melts metal bumps on each wafer’s backside, forming one permanent chip and avoiding the yield issues of a monolithic thousand‑layer die.

To keep alignment precise, Samsung engineered microscopic chucks that counteract wafer warping and introduced new overlay‑correction steps during bonding. Inside the stacked die, revised bitline and wordline architectures curb power consumption while preserving a reasonable footprint, a vital balance for high‑density SSDs aimed at data‑center workloads.

Earlier this year Samsung rolled out its 10th‑generation V‑NAND, surpassing 400 layers per die and debuting hybrid bonding in volume. That platform serves as the launch pad for the bonded 900-layer design, allowing the company to refine manufacturing yields before committing to full‑scale production of the stacked architecture.

Mass production of the 900‑layer stack remains several quarters away; Samsung will first ship the 400‑plus‑layer 10th‑gen chips at volume. Achieving this could push Samsung past SK hynix’s 321‑layer record and deliver denser flash for enterprise servers without a proportional price increase.