Investigation of Space Charge Behavior in Epoxy Resin Substrate of Semiconductor Devices

In recent years, new semiconductor devices using SiC, GaN, etc. that can be operated even at high temperature under high electric field have been developed. While it is possible to miniaturize the equipment by using them, the insulating substrate for the semiconductor element is exposed to a more severe thermal and electrical environment than ever. Therefore, the insulating substrate is required to have high insulating properties at high temperatures. In this research, we focus on epoxy resin to apply them as the substrate, and we especially investigated the space charge accumulation behaviors in them, because they were expected to affect the insulating performance at high temperature under high electric field. In particular, to investigate the effect of impurities in the epoxy resin, space charge distribution measurements were performed on samples that were further annealing after thermosetting. As a result, the annealing under vacuum condition improves the space charge accumulation properties of epoxy resins at temperature of 100 °C.