An Improved Design for 2D Arrays of Capacitive Micromachined Ultrasound Transducers: Modeling, Fabrication, and Characterization

In this paper, we present the design, modeling, fabrication and initial wafer level characterization of Capacitive Micromachined Ultrasound Transducers (CMUTs) with target operating frequencies suitable for medical imaging and therapy. Using finite element analysis, a multilayer stack of thin film materials for the hexagonal shaped cell membrane was studied. An optimized stack in terms of membrane stress and cell size was selected for device fabrication based on a wafer bonding approach. The modelling, fabrication and characterization are treated within this paper.