A Photoacoustic Imaging Device Using Piezoelectric Micromachined Ultrasound Transducers (PMUTs)

IEEE Trans Ultrason Ferroelectr Freq Control. 2020 Apr;67(4):801-809. doi: 10.1109/TUFFC.2019.2956463. Epub 2019 Nov 28.

Abstract

A linear piezoelectric micromachined ultrasound transducer (PMUT) array was fabricated and integrated into a device for photoacoustic imaging (PAI) of tissue phantoms. The PMUT contained 65 array elements, with each element having 60 diaphragms of [Formula: see text] diameter and [Formula: see text] pitch. A lead zirconate titanate (PZT) thin film was used as the piezoelectric layer. The in-air vibration response of the PMUT array elements showed a first mode resonance between 6 and 8 MHz. Hydrophone measurements showed 16.2 kPa average peak ultrasound pressure output at 7.5 mm from one element excited with 5 Vpp input. A receive sensitivity of ~0.48 mV/kPa was observed for a PMUT array element with 0 dB gain. The PMUT array was bonded to a custom-printed circuit board to enable compact integration with an optical fiber bundle for PAI. A broad photoacoustic bandwidth of ~89% was observed for the photoacoustic response captured from absorbing pencil lead targets. Linear scanning of a single element of a PMUT array was performed on different tissue phantoms embedded with light-absorbing targets to successfully demonstrate B-mode PAI using PMUTs.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Equipment Design
  • Micro-Electrical-Mechanical Systems / instrumentation
  • Microtechnology / instrumentation*
  • Phantoms, Imaging
  • Photoacoustic Techniques / instrumentation*
  • Transducers
  • Ultrasonography / instrumentation*