Direct plated copper diamond substrates and their heat dissipation applications for laser diodes

With the increase in the power density of electronic devices, the traditional packaging substrate cannot meet the heat dissipation requirements for high-power devices. Enhancing the heat dissipation capacity of packaging substrate has become the great challenge in the field of electronic packaging. Diamond is the most suitable material for packaging substrates because of high thermal conductivity, high strength and hardness. So, the DPC diamond substrate was prepared to improve the heat dissipation capability of the packaging substrate. DPC diamond substrates exhibit excellent mechanical properties and heat dissipation ability. The shearing strength between the Cu layer and diamond substrate was up to 30 MPa. The light power of infrared LDs packaged with diamond substrates reaches up to 51.5W, which is 8.4% higher than that of AlN substrates (47.5W). The conversion efficiency of infrared LDs packaged with diamond substrates reaches 43.03% at the current of 65 A, which is 26.1% higher than that of AlN substrates (34.12%). Under a high current of 4.0 A, the light power of blue LDs packaged with diamond substrates is 7.39 W, which is 29.4% higher than that of AlN substrates (5.71 W). The conversion efficiency of blue LDs packaged with diamond substrates reaches up to 44.1% with 2.0 A, which is 17.6% higher than that of AlN substrates (37.5%). It can be seen that the diamond substrate is an efficient approach to enhance heat dissipation and improve the performances of high-power devices.