SK Hynix Launches 'iHBM' HBM with Built-In Cooling

SK Hynix announced on the 26th the launch of its new generation high-bandwidth memory cooling technology "iHBM", which integrates cooling components inside the HBM packaging to reduce thermal resistance by more than 30%, and plans to apply it first to next-generation products such as HBM5.

With the explosive growth in AI computing demand, HBM is evolving along two main lines: the continuous increase in the number of stacked layers and the continuous improvement in data transfer rates. However, the price of performance improvement is an increasingly severe thermal management challenge - the faster the chip, the more heat it generates.

Against this backdrop, the "D2D PHY" interconnection area between the HBM base die and the AI acceleration chip has become the core of the cooling bottleneck. This area has a high current density and limited space, and the traditional packaging structure cannot effectively export heat, directly affecting the system's stability and performance under continuous high loads.

The iHBM technology introduced by SK Hynix this time is based on a new structure called ICE (Integrated Cooling Elements).

ICE uses a non-conductive but highly thermally conductive silicon-based material to create an independent heat discharge channel for the D2D PHY area inside the HBM packaging. Its design logic is quite ingenious: it must conduct heat away without interfering with the electrical signals between the chips. The balance between insulation and thermal conductivity is the key.

According to data disclosed by SK Hynix, iHBM can reduce thermal resistance by more than **30%** compared to traditional solutions, maintaining stable operation under high-temperature and high-load environments, directly addressing the stringent requirements of AI data centers for long periods of full-load working scenarios.

The company states that iHBM is based on the **MR-MUF (Mass Reflow-Molded Underfill) wafer-level packaging process** that has been fully validated in the market, and has the ability to directly enter mass production without rebuilding production lines. More importantly, the technology is highly compatible with customers' existing SiP (System in Package) design environment, allowing for importation **without significant modifications to existing system designs**, significantly reducing the switching costs and technical integration difficulty for customers.

These two points mean that iHBM is not a distant roadmap promise, but an engineering solution that is ready for industrialization.

SK Hynix plans to officially introduce iHBM technology from next-generation products such as HBM5, targeting AI data centers and high-performance computing (HPC) applications that require the most stringent thermal management.

SK Hynix Vice President Lee Kang-uk said: "iHBM is a solution that minimizes heat generation by deeply integrating memory design capabilities with advanced packaging technology, which will further consolidate the company's leadership position in the AI memory field."

In the HBM race, SK Hynix has established a leading position with HBM3E and continues to supply to top customers such as Nvidia. The release of the iHBM technology is a clear signal that the company is opening a second battleground beyond "performance" – **when the competition for computing power enters deep water, whoever can solve the heat dissipation problem will hold the ticket to the next generation of AI infrastructure.**