Measurements of charge distributions in insulation materials of power electronics equipment irradiated by proton / electron

Recently, the high performance and high reliability materials on the power electronics devices have been studied. Those devices are used in severe environments, such as high temperature, radiation, vacuum environment, and so on. In this study, we focused on the effect of space charge accumulation in the bulk of dielectrics by the radiation, such as the proton and/or the electron beams. So, we measured space charge distributions on insulating materials for the power electronics devices irradiated by proton/electron using the pulsed electroacoustic (PEA) method. As a result, the charges due to irradiated protons and electrons were confirmed to accumulate in the bulk at the calculated penetration depth, and the electric fields were emphasized 1.3 and 1.2 times larger than that of non-irradiated samples for the proton and electron irradiations, respectively. It is considered that those appearances of the electric field distribution had been occurred by charge accumulation by irradiation, modification of molecules structure, radio activation, and an increase of conductivity. To clarify this assumption, further investigation will be carried out in our future study.