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Electro-acoustical characterization procedure for cMUTs.

Marta Buigas·Francisco Montero de Espinosa·Georg Schmitz·Iñaki Ameijeiras·Pedro Masegosa·Manuel Domínguez
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Abstract

A procedure for the electro-acoustical characterization in air of cMUTs is reported. First, the measured input electrical impedance of the transducer is used to calculate the transducer parameters at different bias voltages by fitting it with the Mason model. Then, the single membrane equivalent circuit can be calculated. Second, the cMUT impulse response is obtained through a send-and-receive experiment to be compared with the one predicted by the Mason model. In order to minimize the influence of the emitter in the obtained impulse response an ad hoc broadband piezoelectric transducer centered at the resonant frequency of the cMUT was fabricated. Using this transducer, no deconvolution of the impulse response of the emitter in the cMUT reception pulse is necessary. The procedure is tested for two cMUTs with silicon-rich nitride as structural layer and different membrane diameters (60 and 70 microm).

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Electric CapacitanceEquipment DesignEquipment Failure AnalysisMiniaturizationReproducibility of ResultsSensitivity and SpecificityTransducersUltrasonographyJournal ArticleResearch Support, Non-U.S. Gov't

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Marta Buigas, Francisco Montero de Espinosa, Georg Schmitz, Iñaki Ameijeiras, Pedro Masegosa, Manuel Domínguez. 2005. Electro-acoustical characterization procedure for cMUTs.. https://doi.org/10.1016/j.ultras.2004.07.006

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