SK hynix pushes hybrid bonding HBM5 as AI memory hits 775-micron ceiling — firm extends MR-MUF through Nvidia Rubin
The problem, per SK, is that HBM cubes are capped at a total thickness of 775 microns, the standard thickness of a 300mm logic wafer.
SK hynix anticipates hybrid bonding to not be available for HBM4E, with the industry's anticipated memory packaging transition shifting to HBM5. HBM cubes are limited to a total thickness of 775 microns, making it necessary to use thinner dies and narrower gaps for additional DRAM layers. SK hynix's mass reflow-molded underfill (MR-MUF) process faces challenges in filling these smaller gaps while controlling warpage on sub-50-micron dies.
Hybrid bonding is currently still in the research stage for stacks of 20 layers and above, with SK hynix deciding which product will be first to implement it. The iHBM concept, which embeds thermally conductive blocks into the base die's die-to-die PHY region, aims to reduce thermal resistance and has been benchmarked against Samsung's Heat Path Block approach and Micron's base-die circuit redesign.
Written by urgent.news from Tom's Hardware's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
