This thesis describes the characterization and modeling of capacitive micromachined ultrasonic transducers (cMUTs). Computational models of two transducer designs were produced through the combined use of finite element analysis (FEA) and lumped element modeling. Frequency response plots were generated for both single element transducers as well as transducer arrays. Through the use of laser Doppler velocimetry, frequency response tests were performed and compared to model predictions. The computational predictions for both coupled and uncoupled arrays were also compared.;The hybrid finite element/lumped element model was shown to be computationally efficient, predicting the resonant frequency within 20% of the experimental results, as well as providing reasonable fractional bandwidth values. The computational model also correctly predicted variations in the frequency response with changes in the transducer's passivation layer material. It was also determined that coupling through the acoustic medium had a profound effect on the frequency response of arrays, greatly increasing fractional bandwidth and decreasing primary resonance of the transducers.
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