Quantum Chemical Calculation Analysis of Electric Charge Trap Site in Epoxy Resin Cured Using Novel Imide Type Hardener

Space charge accumulation characteristics in some newly developed epoxy resins at high temperature under high DC stress were investigated. While various epoxy resins are used as semiconductor packaging materials, it is expected to be improved to be available in a much severer condition under higher DC stress at higher temperatures because some semiconductor have improved to be used under such condition. For this reason, some new type epoxy resins, which are cured using some novel imide type hardeners, have been developed, and they show a high glass transition temperature. In this paper, we tried to estimate the insulating performance of them as the insulating materials at high temperatures under high electric stress. To evaluate them, the space charge accumulation characteristics in them were especially studied because the space charge accumulation is one of signs to show the materials is exposed to some situation as dangerous. As a result, it was found that the space charge accumulation is suppressed in the developed epoxy resins even at high temperatures under high DC stress. To understand the result, quantum chemical calculation analysis was also performed. Calculation results indicate that the developed epoxy resin has a deeper trap than that in the ordinary resin.