SK hynix Reportedly Faces Difficulties in HBM Hybrid Bonding, Trailing Samsung - TechPowerUp

The HBM4 transition window is here, and hybrid bonding has shifted from optional to mandatory — beyond 16-layer stacks, microbump physics caps bandwidth. SK hynix's stumble on this node exposes a structural weakness in its asset-light packaging model. Samsung's vertical integration — in-house fabs plus back-end lines — grants system-level synergy in bonding alignment and thermal management. This is an engineering-capability gap, not a single-process shortfall. On the supply chain, hybrid bonding equipment remains heavily dependent on European vendors like BESI and EVG. Export-control spillover effects are stretching lead times and complicating software licensing. If SK hynix fails to qualify its production line by end-2025, first-wave HBM4 allocations will tilt toward Samsung and Micron. 12-to-24-month outlook: Samsung will likely deploy a yield-for-share strategy, pricing 5-8% below competitors initially, then locking in both cost and performance dominance once yield ramps. SK hynix's window to respond is razor-thin — either crack the bonding process or pivot toward chiplet-based heterogeneous integration to hedge risk. The erosion of HBM's one-dominant-player structure will arrive sooner than consensus expects.