Low dielectric constant of MeV ion-implanted poly(vinylidene fluoride)

Abstract

Poly (vinylidene fluoride) (PVDF) samples were implanted by using high energy (MeV) F 2+ and Cl 2+ ions. We observed that AC dielectric constant of the ion-implanted PVDF samples decreased from 10.5 to 2.5 at 1 kHz as the ion dosage increased from 10 11 to 3Ý 10 14 ions/cm 2 . From differential scanning calorimetry experiments, we observed that PVDF samples become more disordered state through the ion implantation. The decrease of the number of bonding of C-H and C-F and the increase of unsaturated bonding were observed from X-ray photoelectron spectroscopy experiments. The emission of HF and H 2 molecules during the ion implantation was detected by residual gas analyzer spectrum. Based upon the results, we analyzed that the low AC dielectric constant of the MeV ion-implanted PVDF samples originated from the reduction of polarization due to the structural change of the CF 2 molecules in the MeV ion-implanted PVDF samples.