Flexible Piezoelectric 0-3 PZT-PDMS Thin Film for Tactile Sensing

In this paper, Lead Zirconate-Titanate (PZT)/Poly-dimethylsiloxane (PDMS) based composite is fabricated and characterized for its potential application as a flexible piezoelectric material. Thin films of the composite are prepared by dispersing different volume percentage of PZT particles in cross-linked PDMS matrix. Corona poling of the films is performed to increase the piezoelectric charge constant. X-ray diffraction results indicate that poling aligns the randomly oriented ferroelectric domains in the PZT particles along the poling axis. Piezoelectric voltage response and piezoelectric charge constant values before and after the poling show the improvement in piezoelectricity due to poling. The piezoelectric charge constant, d(33) and magnitude of relative permittivity of the films increase and flexibility of the films decrease with the increase of PZT particle volume percentage in the composite. Results show that for 28 v% PZT composite poled film a d(33) of 78.33 pC/N was achieved with a Young's modulus of around 10 MPa and magnitude of relative permittivity of 10. The film demonstrates effectiveness for tactile sensing by generating charges across the film proportional to the finger pressure applied on them. The easy fabrication process makes the composite a promising candidate to build flexible low cost tactile sensing devices.