Structure Design and Thermal Simulation Analysis of DBC Substrate for High-Power IGBT Module

Abstract

In recent decades, IGBT power modules have developed towards high power density, high integration, and high reliability. The junction temperature of the IGBT power module will increase under input current, which will reduce the reliability of the IGBT power module. Aiming at the thermal properties of the IGBT power module packaging structure, this paper proposes an asymmetrical double-sided heat dissipation IGBT power module with reduced size of the top DBC substrate. Using heat transfer theory and ANSYS finite element analysis method, the effect of DBC substrate structure on the thermal properties of high-power IGBT modules was researched and analyzed. We concluded by simulation experiments that compared with the symmetrical structure IGBT module, the junction temperature of the single-sided heat dissipation IGBT power module has increased by 46.9%. While the junction temperature of the asymmetrical structure IGBT module has increased by only 1.6%. Therefore, the asymmetric structure IGBT module proposed in this paper has excellent thermal conductivity and has the advantages of reducing the size, weight and cost of the module. When the single-sided heat dissipation structure cannot meet the heat dissipation requirements of the high-power IGBT module, it is suggested to use an asymmetric structure double- sided heat dissipation structure.