Abstract：Aluminum SiC composites were widely used in high-power integrated circuit packaging materials due to their high thermal conductivity and low thermal expansion rate. Based on the principle of pressure infiltration and hot isostatic pressing，a new process for preparing high-power IGBT aluminum silicon carbide heat-dissipating substrate was proposed. The innovation of this process are：（1）There is no need to prepare silicon carbide preforms， and direct filling of silicon carbide dry powder，the volume fraction of silicon carbide can be stabilized at 66%-68%；（2）The outer surfaces of the substrate are covered with aluminum metal，which can be mechanically and chemically plated or nickel processing；（3）Ultra-high heat isostatic pressing combined with vacuum die-casting process，the azeotropic pressure is about 100 MPa，which can make the aluminum liquid penetrate into the silicon carbide powder better，significantly reducing defects such as pores and bubbles，and therefore gains better performance. According to the test results，the thermal conductivity of the prepared heat dissipation substrate can be as high as 220 W/m·K and the thermal expansion coefficient is 6.5×10－ 6-7.5×10－ 6/K. The other indexes also meet the requirements.
2020, Vol. 30 
