Miniaturized Ultrasonic Transducer with PMN-PT Embedded into Flexible LCP Substrate for Biocompatible Applications
Research output: Contribution to journal › Research article › Contributed › peer-review
Contributors
Abstract
Emerging ultrasound imaging technologies such as wearables and miniaturized invasive devices require exceptional piezoelectric performance alongside flexibility, small form factors, biocompatibility and scalable production capabilities. To address this, we investigate the embedding of high-performance lead magnesium niobate-lead titanate (PMN-PT) transducers in a flexible and biocompatible Liquid Crystal Polymer (LCP) substrate with integrated conductor tracks. This approach aims to improve mechanical reliability and enable industrial-scale production of compact ultrasound devices. The piezoelectric elements were contacted during the embedding process, involving exposure to heat and pressure, requiring a subsequent repolarization process to restore the piezoelectric behavior. Performance was validated against encapsulated wire-bonded reference samples through electrical impedance measurements and acoustic pitch-catch experiments using a hydrophone in a water tank, with different sound incidence angles. After repoling, the embedded single crystal transducer demonstrated expected piezoelectric behavior in impedance data and achieved a peak negative output pressure amplitude of 4.70 kPa (measured at 10 mm distance in water), compared to 4.45 kPa for the encapsulated wire-bonded reference sample, representing a difference of ≈ 5 %. Directivity patterns showed minimal differences in emission angle, with resonance frequencies varying between prototypes due to the inherent characteristics of different manufacturing approaches in the acoustic stack. This embedding approach shows promising results for miniaturized applications, including external ultrasound wearables and patches, as well as invasive devices such as intravascular and implantable ultrasound systems.
Details
| Original language | English |
|---|---|
| Pages (from-to) | 269 - 275 |
| Number of pages | 7 |
| Journal | IEEE Open Journal of Ultrasonics, Ferroelectrics, and Frequency Control |
| Volume | 5 |
| Publication status | Published - 25 Nov 2025 |
| Peer-reviewed | Yes |
External IDs
| ORCID | /0000-0002-3295-0727/work/198588963 |
|---|---|
| ORCID | /0000-0002-2421-6127/work/198593511 |
| ORCID | /0000-0002-0676-6926/work/198593907 |
| ORCID | /0009-0004-0685-2463/work/198594929 |
| ORCID | /0000-0001-5921-9478/work/198594941 |
| unpaywall | 10.1109/ojuffc.2025.3636834 |
Keywords
Keywords
- Transducers, Acoustics, Ultrasonic imaging, Biocompatibility, Wearable devices, Substrates, Fabrication, Assembly, Reliability, Performance evaluation, Biocompatible, flexible electronics, liquid crystal polymer, medical imaging, miniaturized transducer, PMN-PT, embedded transducer, wearable, IVUS