Abstract
This paper presents piezoelectric polymer films with nanostructures enhance the sensitivity. Instead of electrical-field poled, we poled the poly(vinylidene fluoride-trifluoroethylene) PVDF-TrFE thin film by recrystallized. Compared with electrical-field poled, there are many the advantages of easy process, low cost, and high yield. Combined with Hot-Embossing Nanoimprint Lithography (HE-NIL).We developed the PVDF-TrFE thin film with sub-20 nm nanograss. We used PVDF-TrFE thin film with nanograss applied to flexible nanostructured tactile sensor array. This paper presents recrystallized the PVDF-TrFE flat thin film at different temperature. We used the X-Ray diffraction (XRD) analyzing the β phase of PVDF-TrFE, and the piezoelectric force microscopy (PFM) measuring the negative piezoelectricity. The result showed that recrystallized the PVDF-TrFE at the temperature between the Curie temperature (Tc) the melting temperature (Tm), the degree of crystallinity of β phase and the negative piezoelectricity will be better. We find recrystallized PVDF-TrFE flat thin film at 140 °C for 2 hours is the best parameter for our research, and then combined with sub-20 nm nanostructures in morphology by nanoimprint lithography. We can fabricate the PVDF-TrFE with sub-20 nm nanostructures which have high piezoelectricity and high sensitivity. We used PVDF-TrFE thin film with nanograss applied to flexible nanostructured tactile sensor array. The output voltage of the PVDF-TrFE nanograss is 0.4 V by finger touch which force is about 49 mN. The sensitivity of is 0.0095 V/mN and PVDF-TrFE flat film is 0.0032 V/mN. The response of the developed flexible tactile sensors based on PVDF-TrFE nanograss film is 2.96 times larger than the PVDF-TrFE flat thin film. Comparison with other paper is 11.17 times larger. Key Word: PVDF-TrFE, Recrystallized, Curie temperature, Melting temperature, Sub-20 nanometer high-aspect-ratio nanostructures.