Bending characteristics of ferroelectric poly(vinylidene fluoride trifluoroethylene) capacitors fabricated on flexible polyethylene naphthalate substrate

Ferroelectric capacitors using poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)] were fabricated on the plastic polyethylene naphthalate (PEN) substrate for the various applications of flexible-type nonvolatile memories. It was successfully confirmed that the Au/P(VDF-TrFE)/Au capacitors showed sound ferroelectric characteristics even when they were fabricated using a lithography-compatible patterning process at low temperature below 150 °C in the PEN. The behaviors of ferroelectric polarization and saturation as a function of the applied electric field were not so sensitive to the changes in bending curvature radius. However, because small variations in switching properties for the polarization reversal were also observed especially for higher frequency and lower voltage regions, suitable operation schemes should be designed for the flexible memory devices with lower voltage and higher speed operations even at bending situations.