CPU/GPU Stacked Cold Plate Cooling Technology
In order to address the heating issues of high-performance computing and ultra large scale data centers, Fujikura is developing a unique stacked cooling plate as a cooling component for the next generation CPU/GPU. Cold plates with microchannel fin structures, recyclable water, and coolant have been widely used for cooling high-performance CPUs/GPUs. By using thinner microchannel fins and increasing the number of fins, the performance of the cold plate can be improved. However, the thinness of fins is limited by the physical properties of materials and traditional processing methods, so it is necessary to explore new cold plate technologies.
Therefore, Fujikura utilized advanced thermal design methods including topology optimization and metal bonding technology to develop a new type of cold plate with a unique structure. This new type of cold plate is formed by laminating and bonding thin metal plates with a large number of short flow channel characteristics through vacuum brazing. Its internal structure has a large number of three-dimensional narrow and short flow channels, with a high heat transfer coefficient and a larger effective heat transfer area per unit volume.
Compared with traditional cold plates of the same size, the new cold plate reduces thermal resistance by more than 20%, saves space, and achieves efficient cooling, which is expected to contribute to solving cooling problems in various HPC and data center applications.
This type of laminated cold plate can be manufactured in vacuum brazing equipment. In the vacuum high-temperature furnace of the equipment, the lower melting point metal filled between the metal plates is melted into the joints of the cold plates through capillary action, thereby sealing the neatly stacked multi-layer metal plates. By vacuuming, the atmosphere in the high-temperature furnace is eliminated, preventing the formation of oxides during the general brazing process. If there is no vacuum environment, flux is needed to protect the formed joint, and vacuum brazing process can form extremely strong joints without any brazing flux, which can ensure the cleanliness of the welded precision structure.
Due to the increasing demand for faster data processing and more complex computing, the power consumption of CPUs and GPUs in data centers continues to rise, posing significant challenges for the industry in managing the heat generated from this. To address this issue, the industry is adopting various technological strategies to improve the performance of cold plates. These improvements include optimizing thermal conductive materials, refining the microchannel structure inside the plate, and improving the overall design to increase the surface area in contact with the heat source.
