Designing transmitting CMUT cells for airborne applications
Date
2014Source Title
IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
Print ISSN
0885-3010
Publisher
Institute of Electrical and Electronics Engineers Inc.
Volume
61
Issue
11
Pages
1899 - 1910
Language
English
Type
ArticleItem Usage Stats
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Abstract
We report a new mode of airborne operation for capacitive micromachined ultrasonic transducers (CMUT), in which the plate motion spans the entire gap without collapsing and the transducer is driven by a sinusoidal voltage without a dc bias. We present equivalent-circuit-based design fundamentals for an airborne CMUT cell and verify the design targets using fabricated CMUTs. The performance limits for silicon plates are derived. We experimentally obtain 78.9 dB//20 μPa@1 m source level at 73.7 kHz, with a CMUT cell of radius 2.05 mm driven by 71 V sinusoidal drive voltage at half the frequency. The measured quality factor is 120. We also study and discuss the interaction of the nonlinear transduction force and the nonlinearity of the plate compliance. © 1986-2012 IEEE.
Keywords
TransducersAirborne applications
Capacitive micromachined ultrasonic transducer
Nonlinear transduction
Performance limits
Quality factors
Silicon plates
Sinusoidal voltage
Sinusoidal-drive voltage
Ultrasonic transducers