Fangzheng Securities: Increased AI computing power forced cooling materials to upgrade diamond cooling ushered in a golden period of development

The Zhitong Finance App learned that Fangzheng Securities released a research report saying that the cooling industry urgently needs new materials with higher thermal conductivity and matching electrical insulation with CTE. As a result, diamond came into view. It has advantages such as thermal conductivity, compatibility with semiconductor materials, and high temperature resistance. Among the three current technology routes, diamond copper has the most outstanding comprehensive advantages. It has stronger processability, controllable cost, and high mass production cost ratio. With its high purity and high controllability, MPCVD has become the mainstream method for large-scale manufacturing of high-end diamond heat sink sheets. The bank estimates that under conservative, neutral, and optimistic expectations, the global market size of diamond cooling for AI chips in 2030 will be 268, 357, and 44.6 billion yuan, respectively.

The main views of Fangzheng Securities are as follows:

AI chip upgrade requires diamond heat dissipation

As the chip manufacturing process approached the physical limit, the industry moved to 2.5D/3D heterogeneous integration to continue performance growth. The 3D stack is composed of multi-layer thin chips. The middle layer is far from the radiator and the heat dissipation path is limited; when the superimposed single chip power consumption exceeds 1000 W and the local heat flow density exceeds 1000 W/cm2, copper heat dissipation (thermal conductivity ~ 400 W/m·k) has reached the physical limit. The industry is in urgent need of new materials with higher thermal conductivity and matching electrical insulation with CTE. As a result, diamond has entered the field of vision.

Advantages of diamond heat dissipation

1) The thermal conductivity of diamond is 3-5 times that of copper. GPUs using diamond heat sinks can reduce the temperature by more than 10℃, increase computing power by 15%-22%, and support a working environment temperature of up to 50℃. 2) Diamond is highly compatible with semiconductor materials such as silicon, gallium nitride, and silicon carbide, which can greatly reduce the thermal stress between the chip and the heat dissipation material. 3) Unlike metal heat dissipation materials such as copper and aluminum, diamond does not cause chip leakage or short circuit problems, nor does it interfere with high-frequency electrical signal transmission. 4) Diamond is resistant to high temperatures > 600 ℃, resistant to corrosion and radiation, and far exceeds that of traditional heat dissipation materials.

Three technical routes for diamond heat dissipation materials

Diamond composites (diamond copper, diamond aluminum, diamond silicon carbide), single crystal diamond, polycrystalline diamond. Single crystal diamond and polycrystal diamond are pure diamond materials. They have ultra-high thermal conductivity and excellent insulation. They can be used in all scenarios of substrates, heat sinks, and microchannels, and focus on high-end ultra-high power cooling requirements. Among diamond-based composites, diamond copper has the most outstanding comprehensive advantages. Compared with pure diamond materials, it has stronger processability, controllable cost, and high mass production cost ratio.

CVD diamond heat sink equipment barrier is high

With its high purity and high controllability, MPCVD has become the mainstream method for large-scale manufacturing of high-end diamond heat sink sheets. Barriers: 1) High-frequency electromagnetic field design determines the spatial distribution uniformity of the plasma; 2) microwave power stability determines the growth rate and defect density of the wafer; 3) chamber sealing and vacuum control determine the amount of impurities introduced; 4) temperature field uniformity control directly determines the stress distribution (warpage) and yield of the wafer.

Data center AI chip demand for diamond cooling

According to DigiTimesAsia's forecast, global data center AI chip shipments will be about 38.05 million in 2026, which is expected to increase to 53.41 million in 2030. 2026 is the first year of commercial application of diamond cooling in the field of AI chips. The penetration rate is expected to be 1%; conservative assumptions are that the penetration rate will increase to 12% by 2030; neutral expectations will increase the penetration rate to 16% by 2030; and optimistic expectations will increase to 20% by 2030. According to estimates, under conservative, neutral, and optimistic expectations, the global market size of diamond cooling for AI chips in 2030 will be 268, 357, and 44.6 billion yuan, respectively.

Investment suggestions: It is recommended to focus on Sifangda, Yellow River Cyclone, China Machinery Precision, Wald, Power Diamond, and Huifeng Diamond.

Risk warning: Industrialization progress falls short of expectations, industry competition increases risks, raw material price fluctuations, geopolitical risks, etc.