Characterization and Modeling of Capacitive Micromachined Ultrasonic Transducers for Diagnostic Ultrasound

Abstract

This paper describes the characterization and modeling of capacitive micromachined ultrasonic transducers (cMUTs). Computational models of the transducers were produced through the combined use of finite element analysis (FEA) and lumped element modeling. Frequency response plots were generated for both transducers in air and water environments. Through the use of laser Doppler velocimetry, transient step response and frequency sweep tests were performed on single array elements. These measurements are compared to the predicted results represented in the models. The computational results for both coupled and uncoupled arrays are compared, and show a significant increase in the array bandwidth due to coupling. Frequency sweep tests were also performed on column array elements, and results were compared between driven and adjacent, non-driven columns.