Hunan Sanan’s diamond-based solution: laser chip thermal resistance reduced by 81.1% compared with ceramic substrates.

As the power density of AI computing clusters continues to rise, thermal-management challenges for high-power lasers are becoming increasingly acute, and conventional cooling solutions are gradually reaching their technical limits when dealing with high heat-flux scenarios. In response to this challenge, diamond materials, owing to their exceptional thermal conductivity, have emerged as a key breakthrough direction in the field of thermal management. Recently, Hunan Sanan, a wholly owned subsidiary of Sanan Optoelectronics, has achieved a critical milestone in the application of diamond-based thermal-sink materials: its diamond thermal-sink substrates have been adopted by customers in civilian RF, civilian radar, laser, and other applications and have entered the stage of small-batch shipments.

Diamond boasts a thermal conductivity exceeding 2,300 W/m·K—five times that of copper and four times that of silicon carbide—making it the material with the highest thermal conductivity known in nature. Its resistivity is as high as 10¹⁴ Ω·cm, endowing it with both electrical insulation and highly efficient thermal conduction. In high-heat-flux applications such as high-power lasers, AI servers, and RF power amplifiers, the integration of diamond has progressed from theoretical validation to practical engineering implementation.

Hunan Sanan is a pioneering enterprise in China that has established a full-chain manufacturing service platform for wide-bandgap semiconductors and has been investing in ultra-wide-bandgap diamond materials for many years. Measured data show that, after adopting diamond heat sinks, the thermal resistance of laser chips is reduced by 81.1% compared with ceramic substrates, and the devices have successfully passed a 1,000-hour aging test. Currently, Hunan Sanan’s product portfolio encompasses polycrystalline diamond substrates, electronic-grade single-crystal diamond substrates, heat-sink-grade single-crystal diamond substrates, and diamond heat-sink boards, among others. These products have entered the stage of practical application in fields such as lasers, filters, high-power LEDs, and power amplifiers, and the company has already secured bulk orders.

Building industrial barriers through end-to-end capabilities

The industrialization of diamond is by no means the result of breakthroughs in a single link; rather, it is a competition of capabilities across the entire value chain. Hunan San’an has already built a pilot production line for diamond, equipped with MPCVD systems, laser cutting machines, grinding and polishing equipment, as well as atomic force microscopes, scanning electron microscopes, X-ray diffractometers, and other testing instruments. This has enabled the company to seamlessly integrate the entire value chain—from crystal growth and wafer fabrication to testing and end-use applications—while securing four related patents. In addition, Hunan San’an has established industry–university–research collaborations with institutions such as Hunan University and the 48th Institute of China Electronics Technology Group Corporation, fostering synergistic advantages in equipment development, material preparation, and end-application fields.

Diamond Full Chain

(Source: Hunan Sanan)