Preparation and characterization of piezoelectric ceramic–polymer composite thick films by aerosol deposition for sensor application

Abstract Lead zirconate titanate (PZT)-based piezoelectric ceramic and polyvinylidene fluoride (PVDF) organic composite thick films (∼20 μm in thickness) were deposited on a 4-in. diameter Pt/Ti/SiO 2 /Si substrate and a 2-in. diameter Ag–Pd/sapphire substrate by aerosol deposition using a single 4-in. size nozzle for use as a tactile-sensor device. The PVDF content was varied from 3 to 10 vol% and the films deposited on silicon and sapphire were annealed at 700 and 900 °C, respectively. The annealed films showed a relatively high density, even at a 10 vol% of PVDF-piezoelectric ceramic composition, as well as good adhesion to the substrate after annealing. The relative dielectric constant of the composite film decreased sharply with increasing PVDF content, while the piezoelectric d 33 coefficient was conserved at a relatively high value. Therefore, the g 33 coefficient increased and showed the highest value at 3 vol% PVDF. The g 33 values of the as-deposited, 700 °C annealed and 900 °C annealed piezoelectric ceramic-PVDF composite films were 7.77, 16.3 and 41.5 (10 −3  m 2 /N), respectively.