HBF: a new tier between HBM and SSD
SK hynix and Sandisk have unveiled the first open standard specification for High Bandwidth Flash (HBF), targeting next‑generation AI infrastructure. Announced at FMS 2026 in Santa Clara, the spec formalizes HBF as a new memory tier that bridges high‑bandwidth memory (HBM) and solid‑state drives (SSDs).
HBF combines NAND flash capacity with data‑transfer performance approaching HBM, aiming to relieve bandwidth and capacity bottlenecks in data‑hungry AI inference workloads.
Key points of the initial spec:
- Capacities up to 512 GB per device
- Support for 8‑high and 16‑high stacked NAND dies
- Three bandwidth grades from roughly 0.4 TB/s up to 3.0 TB/s
- Defined electrical characteristics, packaging, reliability, and software I/O guidelines
HBF connects to processors via UCIe (Universal Chiplet Interconnect Express), enabling chiplet‑based integration alongside diverse , , and AI accelerators. The spec is published through the as an industry‑wide , not a proprietary interface. Members of the HBF consortium already include and AI processor designer .
