# SK hynix Seeks Suppliers to Prepare iHBM Cooling for 2029 HBM5

By Simon Yoon

Canonical URL: https://www.tokenpost.com/news/technology/38169
Published: 2026-10-22T18:04:05.000Z
Updated: 2026-10-22T18:04:05.000Z
Section: Technology

> The design places an integrated cooling element near base-die GPU links and can reduce thermal resistance by more than 30%.

SK hynix is consulting suppliers on production plans for its iHBM cooling design, preparing the technology for HBM5 as its roadmap places that memory generation in 2029.

The discussions involve materials, components and equipment companies in South Korea and abroad. They cover iHBM product adoption and mass-production plans. SK hynix is also considering additional suppliers that could improve the design’s performance and manufacturing productivity.

iHBM, introduced in May, places an integrated cooling element (ICE) near the base die’s communication links to a GPU. The element provides another heat-dissipation path. The design can reduce thermal resistance by more than 30%. The cooling material around the links is highly heat-conductive and electrically insulating.

High-bandwidth memory (HBM) stacks DRAM core dies above a base die that carries physical connections for data exchange with a GPU. As computing activity and stack heights increase, heat builds around those links. Heat from the base die must pass through the core dies above it to dissipate, making thermal management a challenge for the stacked design.

iHBM uses wafer-level packaging based on Advanced MR-MUF, a process SK hynix already uses for HBM. Advanced MR-MUF fills spaces between stacked memory chips in one step. The expected supplier structure for iHBM is similar to the existing HBM supply chain, while SK hynix considers adding partners to improve performance and production efficiency.

Other memory makers are also addressing heat near the base die. Samsung Electronics is validating its Heat Path Block around the die-to-die physical layer in HBM4E and plans to use it in HBM5. HBM’s thermal challenge is a power-density issue rather than a total-power issue, with heat concentrated in the base die’s logic-heavy areas.

SK hynix is validating HBM5 using Taiwan Semiconductor Manufacturing Co.’s CoWoS advanced packaging technology. Its roadmap places HBM5 in 2029, the generation targeted for iHBM.