Characterization of polyester films used in capacitors. II. Effects of heat treatments on transient and steady-state charging currents in polyethylene terephthalate thin films

Publisher Website
Google Scholar
Abstract
The effects of various heat treatments performed before or after the vacuum deposition of aluminum electrodes on the charging currents flowing through polyethylene terephthalate (PET) thin films (6 and 12 μm) were studied. The amorphous phase of the PET films was characterized by the use of thermally stimulated current/relaxation map analysis spectrometry, allowing precise determination of thermodynamic and thermokinetic parameters. Density measurements were used to calculate the rate of crystallinity achieved after annealing. A correlation was found between the relaxation parameters of the α dipolar relaxation of PET, the rate of crystallinity, and the properties of the charging currents observed from room temperature to 200 °C. Strain-induced crystallization has been put forward to account for the experimental evidences.