Research on the charge trap in polymer by optical and thermal methods

The distribution of charge trap in polyethylene was studied by means of photo-stimulated discharge (PSD) and thermally stimulated discharge (TSD). The shallow trap of 0.77eV in the analysis of TSD comes from the same trap distribution as the deep trap of the depth from 4.80 to 5.90eV in PSD. The results showed that the trap itself is suffered from thermal erosion in the process of charge released by heat. PSD method is considered to be a more accurate method on investigating the trap levels in dielectrics.