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Title: Improving PMUT Receive Sensitivity via DC Bias and Piezoelectric Composition
The receive sensitivity of lead zirconate titanate (PZT) piezoelectric micromachined ultrasound transducers (PMUTs) was improved by applying a DC bias during operation. The PMUT receive sensitivity is governed by the voltage piezoelectric coefficient, h31,f. With applied DC biases (up to 15 V) on a 2 μm PbZr0.52Ti0.48O3 film, e31,f increased 1.6 times, permittivity decreased by a factor of 0.6, and the voltage coefficient increased by ~2.5 times. For released PMUT devices, the ultrasound receive sensitivity improved by 2.5 times and the photoacoustic signal improved 1.9 times with 15 V applied DC bias. B-mode photoacoustic imaging experiments showed that with DC bias, the PMUT received clearer photoacoustic signals from pencil leads at 4.3 cm, compared to 3.7 cm without DC bias.  more » « less
Award ID(s):
1420620
PAR ID:
10415941
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Sensors
Volume:
22
Issue:
15
ISSN:
1424-8220
Page Range / eLocation ID:
5614
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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