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

Abstract

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.

Keywords

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

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