A Disruptive Thermal Solution for AI Chips: Diamond Heat Sinks

With the rapid advancement of artificial intelligence technology, AI chips are iterating and upgrading at an unprecedented pace, and their computing power density is growing exponentially. From high-performance computing chips for training large-scale neural networks to edge-deployed inference chips, all are facing a common critical challenge—thermal management. Traditional thermal solutions can no longer meet the thermal power density requirements of next-generation AI chips, which often reach hundreds of watts or even kilowatts. The thermal bottleneck has become a key obstacle restricting the continuous improvement of AI computing performance. Against this backdrop, diamond materials with ultra-high thermal conductivity are emerging as a revolutionary solution to break through the thermal flux density limits of AI chips.

The thermal power consumption of the most advanced AI training chips currently available (such as the NVIDIA H100 and Google TPU v4) has exceeded 700 watts, while the thermal flux density in the hot-spot areas inside the chips is as high as 200–300 W/cm², and even over 500 W/cm² in local core regions. Such high thermal flux density has left traditional thermal solutions facing multiple predicaments.

Tailored to the diverse packaging formats and thermal management needs of AI chips, diamond heat sinks can build multi-level, multi-dimensional thermal solutions:

Near-Junction Thermal Layer: Direct Chip Attach (DCA) TechnologyBond micron-thin diamond wafers directly to the backside or hot-spot areas of AI chips, forming a "chip-diamond-heatsink" sandwich structure. This near-junction thermal layer can significantly reduce the thermal resistance from the chip junction to the package surface. Experiments show that compared with traditional copper heat sinks, the diamond near-junction layer can reduce thermal resistance by more than 60% and lower hot-spot temperatures by 40–50℃. Key enabling technologies include: nanoscale surface planarization technology (roughness < 1 nm), low-temperature eutectic bonding or metal interlayer bonding technology, and patterned diamond heat sinks for localized enhancement in hot-spot regions.

3D Packaging Vertical Thermal ViasFor 2.5D/3D packaged AI chips, diamond heat sinks can form vertical thermal channels through structures similar to Through-Silicon Vias (TSVs)—namely the "thermal via" technology. Insert diamond interposers or columnar structures into the gaps between stacked computing chips and memory devices to establish an efficient vertical heat transfer path from the interior of the stack to the outer surface. Meanwhile, the high elastic modulus of diamond can also alleviate the thermomechanical stress between different materials.

Heterogeneous Integration Packaging Thermal SystemsCombine diamond heat sinks with advanced thermal technologies such as microchannel liquid cooling and phase-change cooling to build multi-scale thermal management systems:

Diamond-microchannel hybrid heat sinks: Etch micron-scale fluid channels on diamond substrates, leveraging diamond’s high thermal conductivity to rapidly transfer heat from chips to cooling liquids.

Diamond-vapor chamber integrated modules: Use diamond as the base of vapor chambers to enhance the thermal conductivity of the evaporation section and improve overall phase-change cooling efficiency.

Diamond-thermoelectric cooling (TEC) collaborative systems: Utilize diamond’s high thermal conductivity to optimize heat dissipation at the hot end of thermoelectric coolers, boosting cooling efficiency.

Intelligent Thermal Management System IntegrationIntegrate diamond heat sinks with temperature sensors and dynamic power management units to achieve adaptive intelligent thermal control:

Embed a distributed network of micro-temperature sensors within diamond heat sinks to dynamically adjust the voltage and frequency of different chip modules based on real-time thermal maps.

Combine machine learning algorithms to predict thermal behavior and optimize heat dissipation strategies proactively.

In an era of explosive growth in AI and computing demand, thermal management is no longer a "supporting system" but a core technology that determines the performance, reliability, and energy efficiency of computing systems. Endowed with exceptional thermophysical properties, diamond heat sinks are transitioning from laboratory research to industrialization frontiers. They are expected to break the "thermal barrier" that has long constrained AI chip development, providing a sustainable thermal management solution for next-generation artificial intelligence computing. As material growth technologies and integration processes continue to mature and costs decline, diamond thermal solutions will become a standard configuration for high-end AI chips, driving the advancement of artificial intelligence computing toward a future of higher performance and greater energy efficiency.

CSMH uses the MPCVD method to prepare large-sized and high-quality diamonds,and currently has mature products such as diamond heat sinks, diamond wafers, diamond windows,diamond composite materials,etc.Among them,the thermal conductivity of diamond heat sinks is 1000-2200w/（m.k）, which has been applied in aerospace, high-power semiconductor lasers, optical communication, chip heat dissipation, nuclear fusion and other fields.