Effect of fluid losses and acoustic resonances in CMUTs with vented cavities

Author

Apte, N. ; Park, K.K. ; Nikoozadeh, A. ; Khuri-Yakub, B.T.

Author_Institution

E.L. Ginzton Lab., Stanford Univ., Stanford, CA, USA

fYear

2015

fDate

21-25 June 2015

Firstpage

682

Lastpage

685

Abstract

We report on capacitive micromachined ultrasonic transducers (CMUTs) with vented cavities for varying their bandwidth and sensitivity in airborne applications. The devices are simulated using a finite element model which incorporates viscous and thermal fluid losses in the squeeze film and the vent holes, as well as acoustic radiation and acoustic resonance in the backing. Our model accurately predicts the behavior of such CMUTs. The model is also validated with measurements at elevated pressure.

Keywords

acoustic variables measurement; finite element analysis; micromachining; microsensors; ultrasonic transducers; CMUT; acoustic radiation; acoustic resonance; airborne application; capacItIve micromachined ultrasonic transducer; finite element model; thermal fluid loss effect; vented cavity; viscous fluid loss effect; Acoustics; Aluminum; Cavity resonators; Pressure measurement; Substrates; Vents; Airborne ultrasound; CMUT; Navier-Stokes equations; high pressure; wide bandwidth;

fLanguage

English

Publisher

ieee

Conference_Titel

Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS), 2015 Transducers - 2015 18th International Conference on

Conference_Location

Anchorage, AK

Type

conf

DOI

10.1109/TRANSDUCERS.2015.7181015

Filename

7181015