LFE Doctoral researcher Karem Lozano Montero will give a presentation All Printed Flexible Piezoelectric Pressure Sensor with Interdigitated Electrodes on Wednesday September 16th at 15:25 (CEST) in Flexible Electronics I session hosted by Detlef Bonfert, Fraunhofer EMFT, Germany and Matti Mäntysalo, Tampere University of Technology, Finland.
The study of Lozano et al. demonstrates the potential of additive fabrication technologies to develop low-cost and conformal piezoelectric pressure sensors. Owing to their cost-effective fabrication, skin-conformability, and charge generation, printed flexible piezoelectric pressure sensors based on poly(vinylidenfluoride-co-trifluoroethylene) P(VDF-TrFE) have high potential to be used in affordable, unobtrusive and energy-autonomous systems for various healthcare and robotics applications. This study presents a simple two printing step fabrication process for a thin (overall thickness of ~11 µm) flexible piezoelectric sensor based on an interdigitated electrode (IDE) structure. Inkjet printing is used to fabricate a poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) IDE structure with an electrode gap width of 67.9 ± 9.4 µm and an electrode width of 137.8 ± 17.5 µm on a Parylene-C substrate. This is followed by bar coating a layer of piezoelectric polymer (P(VDF-TrFE)) of 9.6 ± 0.9 µm thick. The optimal electric field for poling the piezoelectric material is 50 V/µm which results in a remanent polarization of 5.2 ± 1.0 µC/cm2. The piezoelectric sensitivity was measured in normal mode obtaining a result of 3.9 ± 0.5 pC/N.