We investigated the effects of annealing temperature and vacuum treatment on the crystallinity and ferroelectric properties of solution-casted poly(vinylidenefluoride-co-trifluoroethylene), P(VDF-TrFE), thick films. We varied the annealing temperature from 70°C to 150°C and achieved high-quality ferroelectric thick films annealed at 130°C. Ferroelectric domains and their properties were confirmed using X-ray diffraction, Fourier transform infrared spectroscopy with attenuated total reflection mode and ferroelectric/piezoelectric measurement systems. Drying and/or annealing in the vacuum allowed for the improvement of crystallinity and ferroelectric/piezoelectric properties. Importantly, the piezoelectric coefficient, d33, of our optimal P(VDF-TrFE) films after sufficient poling treatment was 36 pC/N and our P(VDF-TrFE) power generator produced an output voltage of ∼6 V under periodic bending and unbending motions. POLYM. ENG. SCI., 54:466–471, 2014. © 2013 Society of Plastics Engineers