FEM of Air-Coupled Circular Capacitive Micromachined Ultrasonic Transducer for Anodic Bonding Process using SOI Wafer

Gurpreet Singh Gill, Sanjay Kumar, Ravindra Mukhiya, Vinod Kumar Khanna


In this paper, Finite Element Method (FEM)-based design and simulation of circular capacitive micromachined ultrasonic transducer (CMUT) has been discussed. The FEM simulation of CMUT is accomplished by using MEMCAD tools CoventorWare® and COMSOLTM. The simulation has been performed for air-coupled CMUT devices in which the resonance frequency of the designed CMUT device is 3.9 MHz. Moreover, the simulation results for resonance frequency and pull-in voltage show good agreement with analytical calculations. Finally, a device layer transfer fabrication process flow is also proposed to develop the MEMS-based CMUT devices.


CMUT; FEM modelling; Pull-in voltage; Resonance frequency; Wafer bonding.

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