Numerical simulation of thermo-stimulated depolarization currents in polyethylene films

Complementary thermo-stimulated depolarization current (TSDC) and PEA measurements have been performed on a low density polyethylene. A bipolar transport model developed formerly to reproduce the behavior of space charge in a low density polyethylene under electrical stress has been adapted to simulate TSDC spectra. The model is one dimensional (sample thickness). Temperature effects have been introduced by using a hopping type of mobility, detrapping and charge injection also having temperature dependencies. The model shows that the surface of the TSDC spectra largely underestimates the total stored charge within the sample. We show that the model is able to reproduce qualitatively some features of the TSDC spectra which appears promising for the future.