Huawei Unveils 122 TB SSD Built with Proprietary Die‑on‑Board Packaging

What the press release claims

Huawei’s latest data‑center offering is a 122 TB SSD assembled with a proprietary Die‑on‑Board (DoB) packaging process. The company says the drive matches or exceeds the capacity you would expect from a 100‑plus‑layer 3D NAND part, even though it does not have access to the latest NAND wafers from mainstream vendors. Huawei positions the product as a solution for rack‑level storage where every gigabyte counts.

What is actually new?

The packaging technique

DoB is not a new concept in principle – it refers to mounting bare NAND dies directly on a printed circuit board and then stacking additional dies on top, with very short interconnects. What Huawei appears to have done differently is twofold:

1. Custom interposer design – Huawei’s board uses a high‑density routing layer that reduces trace length to a few tens of micrometres, cutting latency and power loss compared with conventional wire‑bond or flip‑chip approaches.
2. Automated vertical stacking – The company claims to have built a production line that can align and bond up to 30 dies per stack with sub‑micron precision, something that previously required expensive 3D‑IC equipment.

The result is a dense stack that reaches 122 TB without relying on the latest 100‑layer NAND geometry. In practice, the drive is likely built from multiple 4‑TB or 8‑TB NAND dies (e.g., 16 GB per die) that are densely packed and then addressed as a single logical unit.

Benchmarks and performance hints

Huawei released a brief spec sheet showing sequential read/write speeds of 6.8 GB/s and 5.2 GB/s, respectively, and an IOPS rating of around 900 k for 4 KB random reads. Those numbers sit comfortably within the range of current enterprise NVMe‑oF drives based on 96‑layer NAND, suggesting the DoB stack does not impose a major performance penalty.

Why it matters

• Supply‑chain independence – By avoiding reliance on external 100‑layer NAND foundries, Huawei can continue to ship high‑capacity drives even under export controls.
• Potential cost advantage – If the DoB line can be scaled, the per‑gigabyte cost may drop because the process uses older, cheaper NAND dies that are still in mass production.
• Form‑factor flexibility – The shorter interconnects enable a slimmer module, which could be attractive for dense blade servers.

Limitations and open questions

• Reliability data is missing – Enterprise storage customers will want MTBF, endurance (TBW), and error‑correction capabilities. Huawei has not published any of these figures.
• Thermal management – Stacking many dies on a board can create hot spots. The announcement did not explain how heat is dissipated or whether the drive requires active cooling beyond standard NVMe‑oF enclosures.
• Scalability of the packaging line – Building a high‑precision stacking system is non‑trivial. It remains unclear whether Huawei can produce the drives in volumes that matter to hyperscale operators.
• Compatibility – The SSD uses a standard NVMe‑oF interface, but firmware integration with existing storage stacks will need validation, especially concerning wear‑leveling across the stacked dies.

Context and comparable efforts

Other vendors have explored similar approaches. Samsung’s Hybrid Memory Cube and Intel’s 3D XPoint both used vertical stacking, but they required specialized TSV (through‑silicon via) processes. Huawei’s DoB sidesteps TSV, which reduces equipment cost but may limit how tightly dies can be packed.

For a broader view of alternative high‑density storage, see the recent analysis of Micron’s 176‑layer NAND and Western Digital’s 3D‑stacked SSDs (see the Micron product page and the WD blog post). Those solutions still depend on the latest NAND fab capacity, something Huawei is explicitly trying to avoid.

Bottom line

Huawei’s 122 TB DoB SSD is a pragmatic response to export restrictions rather than a fundamental breakthrough in NAND technology. The packaging tricks allow the company to repurpose older NAND dies into a high‑capacity module that performs on par with contemporary enterprise SSDs. Until reliability, thermal, and supply‑chain scalability are demonstrated, the drive will likely remain a niche offering for customers who can tolerate a longer qualification period.

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Tags: #NANDFlash #ChipPackaging #EnterpriseStorage