Piezoelectric P(VDF-TrFE) film inkjet printed on silicon for high-frequency ultrasound applications
Aline Banquart, Samuel Callé, Franck Levassort, Lionel Fritsch, F. Ossant, Sean Toffessi Siewe, Stéphanie Chevalliot, Arnaud Capri, Jean‐Marc Grégoire
Abstract
We investigated the innovative processing of poly(vinylidene fluoride-trifluoroethylene) P(VDFx-TrFE1-x) (x = 83 mol. %) by inkjet printing to deliver uniform and thickness-controlled layers on silicon substrates. Here, we provide detailed processing steps and optimize film deposition conditions. The thickness coupling factor for a P(VDF-TrFE) film around 11 μm thick was 22%, demonstrating good electromechanical performance after poling. These multilayer structures were specifically for high-frequency, single-element ultrasonic transducer applications. The measurements of electro-acoustic responses were in water. The maximal frequency was centered at 33.2 MHz and had a fine axial resolution at 22 μm, corresponding to a fractional bandwidth at −6 dB of 100%. In the context of technological evolutions aimed at miniaturized devices and integrated electronics, these results allow for the consideration of complex structures such as multi-element transducers for high-frequency imaging applications.