Flexible Dome and Bump Shape Piezoelectric Tactile Sensors Using PVDF-TrFE Copolymer

In this paper, a new mold-transfer method to pattern piezoelectric polymer has been developed and applied to fabricate innovative dome and bump shape polyvinylidene-fluoride-trifluoroethylene (PVDF-TrFE) films. The dome and bump shape PVDF-TrFE films have been successfully fabricated and characterized as a sensing component for flexible tactile sensors. The tactile sensors developed using these polymer microstructures show a high sensitivity which can measure as small as 40 mN force for bump shape sensors and 25 mN for dome shape sensors. The newly developed fabrication method provides a flexible way to pattern the piezoelectric polymer with different shapes and dimensions, including bump and dome shape piezoelectric polymer microstructures. In addition, a selective dc poling method for the PVDF-TrFE film has been developed for fabricating precisely located piezoelectric sensors with minimum crosstalk. The bump and dome shape PVDF-TrFE films developed in this paper can have numerous applications for microcatheters or other minimally invasive biomedical devices.