Hearing aids are not a one-size-fits-all solution to hearing problems; they must be uniquely tuned for each wearer. There are currently no low-cost and/or effective methods for in situ tuning. This paper describes a microelectromechanical-systems (MEMS)-based dual omnidirectional microphone that can be tuned by growing metallic nanostructures. The nanostructures are grown on integrated solid electrolyte layers on a suspended parylene diaphragm using an external bias and tune the MEMS microphones in situ thereby limiting mismatch. In our tests, this tuning improved the directivity index from 3.5 (fair directionality) to 4.6 dB (excellent directionality) in normal (room temperature) operating environments.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)