Optimization of Device Geometry of a Fully-Implantable Hearing Aid Microphone

A. Dwivedi [1], G. Khanna [1],
[1] National Institute of Technology Hamirpur, Himachal Pradesh, India
Published in 2016

The hearing impairment is affecting more than 360 million people all over the world.In India alone, 63 million people suffer from the significant auditory loss. Conventional hearing aids suffer from reliability, practicality and social stigma concerns. The totally implantable devices provide freedom from the social and practical difficulties of using conventional hearing aids. The paper presents the performance optimization of a MEMS capacitive accelerometer microphone for the fully implantable hearing application. A genetic algorithm is employed to optimize the device geometry parameters satisfying the design constraints. The analytical model run on MATLAB® and the simulation model implemented in COMSOL Multiphysics® software show good agreement. Optimization with Genetic algorithm shows enhanced capacitance of 3.14 pF, displacement sensitivity of 2.49 nm/g and capacitive sensitivity of 2.48 fF/g.