Recovery of remanent polarization of poly(vinylidene fluoride-co-trifluoroethylene) thin film after high temperature annealing using topographically nanostructured aluminium bottom electrode

Facile recovery of ferroelectric polarization after high temperature annealing was observed in a poly(vinylidene fluoride-co-trifluoroethylene) (P(VDF-TrFE)) thin film on an etched Al bottom electrode which has a topographically nanostructured surface with hexagonal registry of the recessed hemispherical bowls of approximately $100nm$ diameter. Fairly large remanent polarization of $10μC∕cm2$ was obtained after annealing up to $185°C$ with the etched Al electrode, while the polarization rapidly dropped near the melting temperature of P(VDF-TrFE) $(∼150°C)$ with a flat Al electrode. The topographic electrode is found to facilitate the reorganization of P(VDF-TrFE) crystal under electric field.