CMUT array element in deep-collapse mode

Date
2011
Advisor
Instructor
Source Title
2011 IEEE International Ultrasonics Symposium
Print ISSN
1948-5719
Electronic ISSN
Publisher
IEEE
Volume
Issue
Pages
108 - 111
Language
English
Type
Conference Paper
Journal Title
Journal ISSN
Volume Title
Abstract

Collapse and deep-collapse mode of operations have boosted the pressure outputs of capacitive micromachined ultrasonic transducers (CMUTs) considerably. In this work, we demonstrate a CMUT element operating in the deep-collapse mode with 25 V pulse excitation and without the effects of charge trapping. The fabricated CMUT element consists of 4 by 4 circular cells with 20 μm radius and 1 μm thick plates suspended over a 50 nm cavity. The overall size of the element is 0.190 mm by 0.19 mm. The collapse voltage of the plates is measured to be approximately 3V. By driving the CMUTs with 25V pulses in the deep-collapse mode without any bias, we achieved 1.2 MPa peak-to-peak pressure output on the surface of the CMUT element with a center frequency of 9 MHz and 100% fractional bandwidth. We applied 1000 consecutive electrical pulses with alternating polarity to the element and witnessed no change in the transmitted acoustic pulse. © 2011 IEEE.

Course
Other identifiers
Book Title
Keywords
A-center, Acoustic pulse, Alternating polarity, Array elements, Capacitive micromachined ultrasonic transducer, Collapse voltage, Electrical pulse, Fractional bandwidths, Mode of operations, Peak-to-peak, Pulse excitation, Thick plate, Ultrasonic transducers, Collapsible tubes
Citation
Published Version (Please cite this version)