Impact Analysis of Variation in Geometrical Features on Intrinsic Characteristics of Capacitive Micro-machined Ultrasonic Transducers

Capacitive Micro-machined Ultrasonic Transducers (CMUTs) are the ultrasonic devices which produce better features in contrast to piezoelectric transducers. The intrinsic parameter of CMUT varies with the variation in geometrical dimension of the device. The cavity height and the radius of the CMUT with circular membrane is varied in the lumped parallel plate model for its impact on the parameters. In this paper, analytical model of circular CMUTs is developed and analyzed by using the parallel-plate capacitor equations. The impact of geometrical changes has been discussed with the parametric analysis of deflection, capacitance, pull in voltage and pressure. The results discussed here will be more helpful in deciding the miniaturization limit of the CMUT prior to fabrication.