Relationship between Electric Field Strength Distribution and Dielectric Breakdown Points in Insulating Substrates of Power Modules

Abstract

Silicon carbide (SiC) devices exhibit several advantages such as high withstand voltage, high temperature operation, and low loss compared to conventional Si devices. To utilize the unique characteristics of SiC devices, it is necessary to improve the characteristics of the power module package. In particular, the insulation characteristics of the package depend on the insulating substrates. In this study, we focused on the difference in dielectric breakdown points when the temperature conditions are changed. It was clarified that the factor that affects the withstand voltage may be the internal stress applied to the insulating substrate due to changes in the ambient temperature, in addition to the electric field strength distribution including the triple junctions.