Relation between trapping parameters and ageing based on a new electro-thermo kinetic equation

Ageing process in low-density polyethylene (LDPE) thin films is investigated based on a newly developed model. This paper discusses the effect of trap depth and cross-section at the electrode-insulation interface and the bulk. To specify the mechanism responsible for conduction in the model, the slope of the experimental curve ln(J) = f(E) was used in an electric field region varying from 5kV/mm to 45kV/mm to calculate the dielectric permittivity ε_r of the samples. It was found that the current-voltage characteristic is dominant by Schottky mechanism at the electrode-insulation interface and Poole-Frenkel effect in the bulk of the insulation. The trap energy depth and cross-section at the interface are 1.35 eV and 2.41×10^-16 m² which are greater than in the bulk 1.02 eV and 1.17×10^-21 m². The results also indicate that trap depths and cross-section may be used as aging markers.