Characteristic of space charge distribution under DC stress in glass materials

The characteristics of space charge accumulation under DC stress in glass materials were investigated using the pulsed electro-acoustic method. However, the observed signal was an incomprehensible signal. To understand the observed signal, a measurement of the glass material with a PET film, which was used as a suppression layer for charge injection, was carried out. From this measurement, it is found that hetro space charges were accumulated in glass material under DC stress. One of the reasons for the incomprehensible signal is thought to be a mismatch of acoustic impedance. Therefore, in this paper, the analysis of observed acoustic signal was carried out by calculating the signal ratio at the interface between the sample and electrodes.