Piezoelectric P(VDF-TrFE) film inkjet printed on silicon for high-frequency ultrasound applications

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.

Diagnostic Value of Color Doppler Ultrasonography in Subacute Thyroiditis

“…The highest age of the patients was 68 years old, and the lowest was 22 years old, with an average of (41:31 ± 3:34) years old. Comparing the clinical data of the two groups, there was no significant statistical significance (P > 0:05), and the data were highly comparable [12]. Inclusion criteria: (1) The experimental group was confirmed as subacute thyroiditis by pathological diagnosis.…”

Material jetting for advanced applications: A state-of-the-art review, gaps and future directions

“…The inkjet-printed piezoelectric P(VDF-TrFE) film on silicon was investigated by Banquart et al and electro-acoustic responses of multi-layer structures, which are specifically designed for high-frequency, single-element ultrasonic transducer applications, were measured in water. The results showed that 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% [277]. This can be used in multi-element transducers for high-frequency imaging applications.…”

Inkjet printing P(VDF-TrFE-CTFE) actuators for large bending strains

“…Inks and processes for IJP EAP have been developed for P(VDF-TrFE) in [21], and for both P(VDF-TrFE) and P(VDF-TrFE-CTFE) in [22], whereas the latter study further used sputtering to deposit Au electrodes to produce force sensors. Banquart et al reported IJP a P(VDF-TrFE) layer on a silicon substrate and sputter-coating the top electrode to form ultrasound transducers [23], and Abdolmaleki et al combined IJP of P(VDF-TrFE)-AGO nanocomposites with painting Ag electrodes to form biomedical monitoring sensors [24]. P(VDF-TrFE)-based transducers with IJP'ed Ag electrodes were reported by Alique et al [25], and P(VDF-TrFE-CTFE)-based actuators with IJP'ed carbon black electrodes were reported in [26,27], whereas the EAP layers in these studies were respectively screen-printed and spincoated.…”