Time-Dependent Study of Pressure Waves Generated by Square Array MEMS Ultrasound Transducers

M. A. G. Suijlen [1], R. J. Woltjer [1],
[1] Novioscan, Nijmegen, Netherlands
Published in 2017

For non-imaging wearable ultrasound applications Novioscan is developing piezoelectric MEMS transducers. These transducers consist of a large array of micromechanical silicon membranes with piezoelectrically actuated regions to generate an out-of-plane displacement causing a pressure wave in the adjacent medium. For a typical application of echo sounding in a human body such transducers operate in pulsed transmission mode. We built a simulation model for the time-dependent study of the membrane motion of and the pressure waves generated by such a transducer in the acoustically very similar medium of water. The model deals with the full piezo-acoustics using the Acoustics Module in 3D geometry to find consistent results on acoustic far-field pressure. Furthermore the dependency of this far-field pressure on pulse duration and membrane pitch distance is shown. In conclusion we discuss solution accuracy and the significance of the simulation model for efficient design of these transducers.