The improvement in heat transfer performance of single crystal silicon carbide with diamond film

Abstract

In order to reduce the temperature of SiC-based electronic power devices during operation, the diamond films of different thickness were grown on 4H-SiC substrates by microwave plasma chemical vapor deposition (MPCVD) method. The thermal conductivity of the composite with 92 μm thick diamond film was measured to be 429.97 W/(m·K) by laser flash method, which is 53.56 % higher than that of individual 4H-SiC. The diamond/SiC composite was heated on the heat stage to investigate its heat transfer characteristics. The heat spread performance was improved by more than 10 %, which benefits the reliability and the service life of the electronic power device. The solid heat transfer was also simulated by COMSOL software. It was found that the thicker diamond film, the higher thermal conductivity. The thermal resistance of the interface between diamond and single crystal SiC would lead to the decrease of thermal conductivity of the composite.