Diamond Heat Sink: A High Heat Flux Thermal Management Solution for AI Chips

In recent years, the rapid development of artificial intelligence, large-scale model training, and high-performance computing has driven continuous increases in AI chip power consumption, creating new challenges for data center thermal management. Liquid cooling technology, with its highly efficient heat transfer capability, has become a key thermal management solution for current AI servers. However, as thermal challenges move closer to the chip level, system-level liquid cooling alone is no longer sufficient to fully address localized hotspots within advanced chips. Reducing internal chip thermal resistance and improving heat transfer efficiency have become critical priorities in next-generation semiconductor thermal management. In this context, Diamond Heat Sink has emerged as a promising material solution for high-power semiconductor thermal management due to its exceptional thermal properties.

Why Is Diamond Suitable for Chip Thermal Management?

Diamond is one of the materials with the highest thermal conductivity known today. Compared with conventional metals such as copper and aluminum, diamond offers significantly superior thermal conductivity, enabling rapid heat transfer and spreading of heat generated during chip operation.

In high heat flux applications such as AI chips, localized high-temperature regions, known as hotspots, can easily form inside the device. Persistent hotspots can increase chip temperature, resulting in performance degradation, thermal throttling, and reduced device reliability. Leveraging its outstanding heat spreading capability, Diamond Heat Sink serves as an efficient thermal transport medium between the chip and cooling system, rapidly dispersing concentrated heat and reducing chip junction temperature.

Beyond its excellent thermal conductivity, diamond also features a thermal expansion coefficient compatible with semiconductor materials. During long-term chip operation, continuous temperature fluctuations can generate thermal stress due to differences in thermal expansion between materials, potentially affecting packaging reliability. Diamond’s low coefficient of thermal expansion (CTE) provides better compatibility with semiconductor materials such as silicon and silicon carbide, improving the stability of packaging structures under long-term thermal cycling conditions.

In addition, diamond offers excellent electrical insulation properties. This unique combination of high thermal conductivity and electrical isolation provides significant advantages in applications requiring efficient heat dissipation and electrical insulation, particularly for high-frequency and high-power electronic devices.

Main Application Approaches of Diamond Heat Sink

Depending on different chip structures and application requirements, Diamond Heat Sink can be implemented through various approaches.

1. As an Advanced Packaging Substrate Material

Diamond can be used as a high-performance packaging substrate or thermal substrate, providing an efficient heat transfer pathway for semiconductor devices. With its exceptional thermal conductivity, diamond-based substrates reduce internal thermal resistance and accelerate heat transfer from the chip to external cooling structures.

This approach is particularly suitable for high-power semiconductor devices, power electronics, and high-performance laser systems, improving device operational stability and reliability.

2. As a Chip Heat Spreader or Thermal Management Structure

Diamond Heat Sink can be processed into thin plates or customized structures and directly attached to the backside of chips or placed near heat-generating regions. Through its superior heat spreading capability, it rapidly transfers heat generated by the device.

In applications such as high-power semiconductor lasers, RF devices, and high-performance computing chips, Diamond Heat Sink effectively reduces localized hotspot temperatures, enhances thermal management performance, and supports continuous high-power operation.

3. As a Thermal Management Coating

Through chemical vapor deposition (CVD) processes, diamond thin films can be deposited onto chip surfaces, packaging structures, or other critical heat transfer regions to form thermal management coatings.

This approach improves local heat spreading capability without significantly modifying existing device structures, expands effective heat dissipation areas, and reduces thermal accumulation risks. It is particularly suitable for miniaturized electronic devices requiring both compact size and high thermal performance.

Diamond Heat Sink and Liquid Cooling: A Complementary Thermal Management Solution

Currently, liquid cooling primarily addresses thermal management at the system level by rapidly removing heat released from cooling components. In contrast, Diamond Heat Sink focuses on improving heat transfer from the chip interior to the cooling structure.

The two technologies address different stages of the thermal management chain:

• Diamond Heat Sink: reduces internal chip thermal resistance and improves heat spreading efficiency.

• Liquid cooling system: transports heat efficiently from the cooling structure to the external environment.

In future high-power AI servers, these technologies are expected to form a synergistic thermal management architecture:

Chip heat generation → Diamond Heat Sink rapid heat spreading → Liquid cooling system efficient heat removal

This combination of material-level thermal management and system-level cooling has the potential to further improve the energy efficiency, computing performance, and operational reliability of AI computing infrastructure, providing a more efficient and reliable thermal solution for next-generation AI systems.

CSMH is a national high-tech enterprise specializing in the research, development, manufacturing, and commercialization of wide-bandgap semiconductor materials. Its core product portfolio includes polycrystalline diamond materials (Diamond Wafer, Diamond Heat Sink, diamond window, and diamond-based composite substrates), single-crystal diamond materials (thermal-grade, optical-grade, electronic-grade, and boron-doped diamond), as well as diamond copper composite materials.By driving innovation in diamond and next-generation materials, CSMH enables advanced industrial applications across multiple high-performance sectors. The company’s products are widely applied in laser systems, GPU/CPU thermal management, optical communications, medical devices, 5G base stations, high-power LEDs, new energy vehicles, photovoltaic systems, aerospace, and defense industries.