Hynix to sample HBM3e 16hi in H1 2025

In H1 2025, Hynix is to start sampling HBM3e 16hi memory with 48 GB capacity per cube.

HBM suppliers usually introduce two stack height options  – such as 8hi and 12hi stacks for HBM3e and 12hi and 16hi stacks planned for HBM4 – in  each generation, says TrendForce.

With HBM4 12hi starting in the second half of 2025,  Hynix’s move to add a 16hi option within the HBM3e family could be because TSMC’s CoWoS-L packaging technology is expected to support larger package sizes between 2026 and 2027, allowing for more HBM stacks per SiP.

Before the more demanding production of HBM4 16hi starts, the HBM3e 16hi provides a high-capacity alternative. With up to eight HBM stacks per SiP, HBM3e 16hi can deliver a maximum capacity of 384 GB per system, significantly surpassing NVIDIA’s Rubin at 288 GB.

Transitioning from HBM3e to HBM4 will double the I/O count. This drives higher computational bandwidth while increasing die size, but the per-die capacity remains at 24 GB.

In the upgrade from HBM3e 12hi to HBM4 12hi, the HBM3e 16hi can serve as an option that offers lower I/O, smaller die sizes, and higher memory capacity.

TrendForce says that HBM3e 16hi will adopt the Advanced MR-MUF stacking process. Compared to the TC-NCF process, MR-MUF allows for higher stack counts and greater computational bandwidth.

By producing HBM3e 16hi ahead of HBM4’s 16hi versions, Hynix will get high-stack manufacturing experience that will facilitate a smoother transition to HBM4 16hi production.

Hynix is also considering a future release of a 16hi variant using hybrid bonding, says TrendForce, further expanding high-bandwidth options for advanced computing applications.