As the power consumption and heat flux density of high-performance chips such as GPUs and ASICs continue to escalate, the performance limits of traditional copper and aluminum thermal materials are becoming increasingly apparent. Diamond, with its superior thermal conductivity and low thermal expansion coefficient, is poised to become a vital supplemental thermal material for high-heat-flux devices, according to a research report from Southwest Securities Co.,Ltd. (SSE: 600369).

Currently, three technical routes—diamond-metal composites, polycrystalline CVD diamond, and single-crystal CVD diamond—are advancing in parallel. Enterprises both domestically and internationally have progressed from material research into customer validation, small-batch supply, and production line construction phases. Given the demanding requirements of diamond-based thermal solutions in large-size fabrication, precision machining, interface bonding, and reliability, companies that first complete validation with leading customers and establish stable mass-production delivery capabilities are likely to secure a first-mover advantage.

Near-Chip Heat Dissipation Becomes a Key Bottleneck for AI Computing Advancement

The growth in AI computing demand is driving continuous increases in the single-chip power consumption and localized heat flux density of high-performance chips like GPUs and ASICs. The thermal bottleneck is now shifting from system-level heat exchange to the near-chip heat transfer stage. While liquid cooling enhances system-level heat transport efficiency, multiple layers of thermal resistance—including the chip backside, thermal interface material (TIM), and lid—remain between the chip and the coolant, elevating the importance of near-chip material performance.

As high-power chips accelerate in volume, conventional materials such as copper and aluminum are approaching their performance ceilings, and the demand for materials with higher thermal conductivity is expected to grow steadily.

Diamond's Unique Properties Cover Multiple Industrialization Stages Across Three Technical Routes

Diamond offers a compelling combination of properties: a room-temperature thermal conductivity of 2000–2200 W/(m·K), a thermal expansion coefficient of approximately 1.0–1.5×10⁻⁶/K, along with excellent electrical insulation and high thermal stability. These attributes significantly enhance hotspot spreading and reduce thermal resistance near the junction region.

The industry has formed three primary technical routes: diamond-metal composite materials, which offer advantages in engineering compatibility and cost; polycrystalline CVD diamond, which balances performance with industrialization progress; and single-crystal CVD diamond, which provides a higher performance ceiling. These routes are not simply substitutes for one another but are being introduced in layers as chip power and packaging configurations evolve.

Industrial Foundation Strengthens with Advances in Equipment, Materials, and Application Validation

China has established a relatively complete foundation for diamond fabrication equipment, including HPHT and MPCVD technologies. Supporting capabilities in large-area CVD growth, cutting, grinding, polishing, metallization, and interface bonding are continuously improving, extending the industry chain from traditional superhard materials to high-value-added functional materials.

Meanwhile, validation efforts in downstream applications such as AI/HPC, high-power lasers, RF, and power electronics are progressing. Some diamond thermal products have already entered customer validation, small-batch supply, and production line construction stages, signaling that the conditions for industrialization are gradually maturing.

Competitive Landscape Still Forming as Barriers Extend from Material Growth to Full-Process Integration

The intrinsic thermal conductivity of diamond does not directly equate to the final heat-dissipation performance of a device. Factors such as large-size stable growth, defect and stress control, thinning and polishing, metallization, bonding strength, interface thermal resistance, and thermal cycling reliability all affect product yield and actual cooling effectiveness.

Domestic participants come from diverse backgrounds, including traditional superhard materials, equipment manufacturing, precision machining, and specialized functional materials, each with distinct entry paths. As applications move from standalone heat sinks to chip-backside and wafer-level integration, companies with capabilities in large-size fabrication, precision machining, low-thermal-resistance bonding, and scalable delivery are expected to strengthen their competitive advantages.

Risk Warnings

Risks include lower-than-expected demand for high-computing-power chips downstream, delays in the commercialization and customer validation of diamond thermal solutions, and systemic macroeconomic risks.