[TuP3H] H. Flexible materials

[TuP3H-02] Dielectric Response of P(VDF-TrFE) Thin Films under Controlled Polarization States

〇Yusuke Maeda¹, shinya Kawano¹, Yoshiki Hidaka¹, Kenichi Goushi¹, Kenji Ishida¹ (1. Kyushu Univ. (Japan))

This study investigates the relationship between the molecular orientational state and the polarization response in poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)] thin films, which is one of the promising ferroelectric polymers for flexible electronics applications such as nonvolatile memory and pyroelectric sensors. The dielectric response was evaluated by impedance measurements under a superimposed DC bias voltage. P(VDF-TrFE) thin film capacitors with a metal–insulator–metal (MIM) structure sandwiched between Al electrodes were fabricated, and two polarization conditions, up-poling and down-poling, were prepared prior to the measurements. Under the up-poling condition, where the external electric field was applied parallel to the polarization direction, the relative permittivity decreased monotonically with increasing DC bias. In contrast, under the down-poling condition with antiparallel field application, the relative permittivity initially increased below the coercive voltage, then decreased sharply beyond it. This contrasting behavior originates from the presence or absence of polarization reversal under the applied DC bias. These results demonstrate that impedance spectroscopy sensitively captures both the polarization orientational state and the polarization history of P(VDF-TrFE) thin films, validating this technique as an effective characterization method for evaluating molecular orientational states in flexible ferroelectric devices.