Effect of ionizing radiation on the electrical characteristics of polyvinylidene fluoride (PVF/sub 2/)

The influence of high-energy electron irradiation on the electrical properties of biaxially oriented polyvinylidene fluoride (PVF/sub 2/) film was investigated. The film was irradiated in air with a 1-MeV electron beam at a dose rate of 10/sup 6/ rad/min to different dose levels of up to 10/sup 8/ rad. Electrical properties measured included dielectric permittivity and dielectric loss, AC and DC breakdown voltages, and DC volume resistivity, X-ray diffraction and IR spectroscopy measurements were also made. The most pronounced of the radiation-induced changes were a decrease in like AC breakdown voltage and an increase in dielectric loss, both corresponding to increasing total absorbed dose. DC breakdown voltage and volume resistivity also showed noticeable changes. These changes are believed to be associated initially with a radiation-induced crystal phase transformation. This was confirmed by the X-ray diffraction curve and the IR spectra, which showed an increase in the beta -phase and a decrease in the alpha -phase peaks at higher dose levels.<
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