Time-domain models of MUT array cross-talk in silicon substrates

Micromachined ultrasonic transducer (MUT) arrays are topical because, among other opportunities, they may supplant piezoelectric arrays in ultrasound medical imaging. However, imaging system companies need to explore performance and design issues thoroughly before making a serious commitment to these silicon-based electrostatic devices. To this end, a fully nonlinear, 3D MUT virtual prototyping capability was recently added to PZFlex. It is described here and applied to medical-type arrays. Simple representations of MUT plate vibration, including acoustic loading and radiation, are presented. Array cross-talk through the surface structure and silicon substrate is quantified using large-scale models. Additionally, an intuitive 1D electromechanical MUT model is developed for modeling and design guidance.