Lead zirconate titanate (PZT)-based piezoelectric micromachined ultrasonic transducers (PMUTs) for particle manipulation applications were designed, fabricated, characterized, and tested. The PMUTs had a diaphragm diameter of 60 μm, a resonant frequency of 8 MHz, and an operational bandwidth (BW) of 62.5%. Acoustic pressure output in water was 9.5 kPa at 7.5 mm distance from a PMUT element excited with a unipolar waveform at 5Vpp. The element consisted of 20 diaphragms connected electrically in parallel. Particle trapping of 4 μm silica beads was shown to be possible with 5 Vpp unipolar excitation. Trapping of multiple beads by a single element and deterministic control of particles via acoustophoresis without the assistance of microfluidic flow were demonstrated. It was found that the particles move toward diaphragm areas of highest pressure, in agreement with literature and simulations. Unique bead patterns were generated at different driving frequencies and were formed at frequencies up to 60 MHz, much higher than the operational BW. Levitation planes were generated above the 30 MHz driving frequency.
|Original language||English (US)|
|Number of pages||11|
|Journal||IEEE transactions on ultrasonics, ferroelectrics, and frequency control|
|State||Published - Oct 2019|
All Science Journal Classification (ASJC) codes
- Acoustics and Ultrasonics
- Electrical and Electronic Engineering