Simulation and Fabrication of Compounded CMUTs for Medical Application

This paper reports a compounded capacitive micromachined ultrasound transducer (CMUT), which has the potential of CMUTs for multi-frequency transducer applications and medical application both imaging and therapy. The compounded CMUT has a cell with low and high-frequency structures. we introduce a fabrication method involving two silicon-on-insulator (SOI) wafers. The performances of CMUTs are strongly dependent on the geometrical properties of the single cells and their arrangement within each element as well. Our devices are modeled using a finite-element package. Finite element simulations about parametric studies are used for analysis, design, and optimization of CMUT cells to predict device performance. Measured deflections show excellent agreement with modeled performance. Keywords-compounded capacitive micromachined ultrasound transducers; multi-frequency; MEMS; ultrasound; medical application