High gamma dose response of the electrical properties of polyethylene terephthalate thin films

Electrical properties of polyethylene terephthalate (PET), irradiated with gamma rays, have been investigated. The PET films were irradiated with high gamma dose levels in the range from 100 to 2000 kGy. The changes in the DC (σ_DC) and the ac (σ_ac) conductivities, with the dose, have been performed. The effect of gamma irradiation on the dielectric constant (ε′) and loss (ε″) has been determined. Also, the dose dependence of the frequency exponent index (S), the resonance frequency (Fc) and the hopping frequency (ω_P) have been obtained. The obtained results show that increasing gamma dose leads to slight increase in σ_DC, σ_ac and ε′, while no change was observed in ε″ value. Meanwhile, S, Fc and ω_P are inversely proportional to the dose. Accordingly, the study suggests the possibility of using PET films in electronic components (capacitors, resistors, etc.), especially that operate at high gamma dose environments for the frequency independent applications.