Application of direct deposition diamond wafer technology in laser crystal thermal management

Laser crystal is the core component of laser technology, which can convert external energy into parallel light, and is the main component of laser crystal. Diamond has the highest thermal conductivity among known materials. Directly depositing diamond film on the surface of laser crystal can effectively improve the heat transfer ability of laser crystal, which greatly reduces the technical cost compared with the bonding process.

Recently, the crystal center has made progress in laser crystal thermal management. On the basis of previous work, researchers proposed the use of metal Cr transition layer to deposit diamond polycrystalline film on titanium sapphire. The Cr transition layer can effectively alleviate the lattice mismatch and thermal mismatch between diamond and titanium gem, and improve the interfacial bonding ability. The researchers have successfully prepared a complete and uniform polycrystalline diamond film with a thickness of 51 μm on a titanium sapphire substrate by microwave plasma chemical vapor deposition ( MPCVD ). The internal stress of the film is 0.97 GPa, and the thermal expansion coefficient of the titanium sapphire sample after depositing the diamond film is increased by 17 %. At the same time, the formation of C-Cr bond at the interface was revealed by first-principles calculations. Direct diamond deposition technology is expected to be more widely used in the field of laser crystal thermal management.

CSMH focuses on the research and production of diamond wafers. At present, it has diamond wafers, diamond heat sinks, GaN on diamond, AlN on diamond and other products. Among them, high-power semiconductor lasers packaged by diamond heat sinks have been used in optical communications. In the fields of laser diodes, power transistors, and electronic packaging materials, it can provide customers with diamond thermal management solutions.