Ferroelectric Properties of Polyvinylidenefluoride-Trifluoroethylene (PVDF-TrFE) Annealed Thin Film

Abstract

The annealing temperature for 250nm PVDF-TrFE (70:30 mol %) spin coated thin films were varied at solvent evaporation (Ts = 79°C), Curies transition (Tc= 113°C) till melting temperature (Tm = 154°C). From the XRD measurement, there was an improvement in the crystallinity of the annealed films, consistent with the increased in the annealing temperatures. Morphological studies of the annealed PVDF-TrFE thin films as observed with Field Emission Scanning Electron Microscope (FESEM) (100k magnification), showed enhanced development of elongated crystallite structures better known as ferroelectric crystal. However, the AN160 thin film showed fibrous-like structure with appearance of nanoscale separations, which suggested to posed high possibility of defects. Ferroelectric characterization indicated an improvement in the remnant polarization of annealed PVDF-TrFE thin films with the exception to AN160 in which leakage of current was inevitable due to the presence of cracks on the film surface.