Optimization of MEMS Based Capacitive Accelerometer for Fully Implantable Hearing Aid Application

A. Dwivedi [1], G. Khanna [1],
[1] NIT Hamirpur, Hamirpur, Himachal Pradesh, India
Published in 2015

This work describes the design and optimization of three prototypes of microelectromechanical systems (MEMS) capacitive accelerometer-based middle ear microphone. The microphone is intended for middle ear hearing aids as well as future fully implantable cochlear prosthesis. The analysis is done using COMSOL Multiphysics®. The maximum applied acceleration was considered 1g. Human temporal bones acoustic response characterization results are used to derive the accelerometer design requirements. The accelerometer can be attached to the middle ear bone structure, umbo to convert the bone vibration to an electrical signal representing the original acoustic information. The capacitance sensitivities and capacitance values of three different prototypes with different gap spacing between fixed and movable electrodes is considered for optimizing the design.