Samsung Unveils First HBM5 Prototype with Heat Path Block Cooling at Computex

Heat Path Block: Redefining In‑Package Cooling

Samsung Electronics displayed its inaugural high‑bandwidth memory (HBM5) mockup on June 3, 2026, at the Computex trade show in Taipei. The prototype pairs the next‑generation memory stack with a novel Heat Path Block cooling system, targeting the same die‑to‑die hotspot that rivals SK hynix are also trying to tame.

The new design integrates a thin copper‑based heat spreader directly onto the HBM5 stack, creating a low‑resistance path for thermal energy to exit the densely packed dies. Samsung says the approach reduces peak temperature by up to 15 °C compared with conventional backside cooling. The move reflects a broader industry push to boost bandwidth while keeping power budgets tight, as AI accelerators and large‑scale GPUs demand ever‑greater memory performance.

Samsung’s Heat Path Block is a monolithic copper slab etched with micro‑channels that align with the memory stack’s active regions. Heat generated by each die travels through these channels to a dedicated heat sink mounted on the package substrate. „Our goal was to keep the thermal gradient flat across the entire stack,” said Dr. Min‑soo Lee, Samsung’s senior vice‑president of memory technology. „By routing heat straight from the hotspot, we avoid the bottleneck that traditional backside cooling creates.”

The prototype measures 1.2 mm thick, fitting within the standard HBM package envelope. Early thermal simulations suggest the system can sustain data rates exceeding 1 TB/s per stack while maintaining a 70 °C operating ceiling. Samsung plans to validate the design with full‑scale production chips later this year, aiming for volume shipments in 2027.

Can SK hynix Match Samsung’s Thermal Solution?

SK hynix, Samsung’s chief competitor, has announced its own in‑package cooling concept called the „Thermal Bridge.” The technology uses a graphene‑enhanced interposer to spread heat laterally before it reaches the package’s outer surface. Industry analysts note that graphene’s high thermal conductivity could rival copper, but scaling the material for mass production remains a challenge.

„Both companies are converging on the same problem: how to evacuate heat from a shrinking die‑to‑die gap,” observed Maya Patel, a semiconductor analyst at TechInsights. „Samsung’s copper‑based block is proven and manufacturable, while SK hynix’s graphene bridge is still experimental. The winner will likely be the one that can integrate the solution without adding significant cost or thickness.”

The rivalry is intensifying as major AI chip makers, such as Nvidia and AMD, signal readiness to adopt HBM5 in upcoming products. Whichever cooling method proves more reliable could shape the memory market’s direction for the next decade.

Frequently Asked Questions

The debut of Samsung’s Heat Path Block marks a pivotal step toward overcoming the thermal ceiling that has limited HBM generations. If the technology scales, it could unlock higher bandwidths without sacrificing power efficiency, giving AI and high‑performance computing platforms a decisive edge. Meanwhile, SK hynix’s parallel efforts suggest the competition will drive rapid innovation, benefitting manufacturers and end users alike.

What is the main advantage of the Heat Path Block over traditional cooling? It creates a direct thermal conduit from the memory die to the heat sink, lowering peak temperatures by up to 15 °C and allowing higher data rates.

When will Samsung’s HBM5 with this cooling system be available commercially? Samsung aims to complete validation in late 2026 and begin volume production for 2027‑2028 product cycles.

How does SK hynix’s Thermal Bridge differ from Samsung’s approach? SK hynix relies on a graphene‑enhanced interposer to spread heat laterally, whereas Samsung uses a copper slab with micro‑channels for vertical heat extraction.