Diamond wafer helps improve the performance of VCSEL laser

According to global data in recent years, VCSEL laser emitters are the most popular among semiconductor lasers. Since the successful application of VCSEL in the Iphon mobile facial recognition module in 2017, it has received widespread attention. Meanwhile, due to power enhancement, it has also begun to be applied in medium and long-distance fields such as lidar and security lighting.

Compared with solid-state lasers, fiber lasers, and other technologies, VCSEL semiconductor lasers have a higher electro-optical conversion efficiency, reaching 40% to 60%. Even so, they still generate a large amount of heat during operation. If the heat dissipation effect is not good, it will cause an increase in chip temperature - directly affecting the output power, threshold current density, electro-optical conversion efficiency, differential quantum efficiency, polarization degree and other performance of the semiconductor exciter, And it can lead to a decrease in the lifespan and reliability of semiconductor lasers, and even damage chips. Good heat dissipation is one of the key factors in ensuring the power and beam quality of semiconductor lasers.

The thermal resistance of the laser is inversely proportional to its thermal conductivity, and the higher the thermal conductivity of the heat sink material, the more effective it is to reduce the thermal resistance of the device. Considering the above factors, heat sink materials such as aluminum nitride, aluminum oxide, and diamond have emerged. Their applications can improve heat dissipation capacity, reduce thermal resistance, increase laser output power, and extend laser lifespan.

In many application fields, excessive heat sink requires the use of diamond, whose thermal conductivity can reach 1000-2200W/(K · m). Compared with aluminum nitride transition heat sink with thermal conductivity of 140-230W/(K · m), diamond heat sink can significantly improve the heat dissipation effect of lasers; But compared to diamond heat sink, the thermal mismatch of using aluminum nitride heat sink to package chips is lower (based on data such as thermal expansion parameters). Therefore, when using diamond heat sink as a transition heat sink packaging laser, there are certain requirements for the solder, and it is necessary to choose a suitable solder to reduce the thermal stress introduced by thermal mismatch.

Diamond wafer is an ideal material for electronic heat sink components, with a thermal conductivity five times that of copper. It can meet various thermal applications and has been widely used in the production of heat sinks for laser diodes, laser diode arrays, high-power semiconductor devices, microwave devices, and large-scale integrated circuits. CSMH focuses on diamond production and research, with world-class diamond manufacturing technology and innovative diamond atomic level surface efficient and precision machining methods. The surface roughness of diamond wafer is reduced to below 1nm, which can meet the heat dissipation needs of most electronic heat dissipation devices.