SBIR Phase II: High Performance Directional MEMS Microphones for Communication Devices

Silicon Audio, Llc, Austin TX

Investigators

Abstract

This Small Business Innovation Research (SBIR) Phase II project will investigate a novel Micro-electro-mechanical systems (MEMS) microphone based on new design principles. By abandoning the design principles of traditional microphones (both MEMS and full-scale), a vastly superior acoustical design is being explored that has resulted in substantial improvements in fidelity and size reduction (15 dB signal to noise ration[SNR] improvement over existing commercial directional microphones, and roughly 100x smaller in volume). Furthermore, as demonstrated in Phase I, the microphones have an inherently directional response with the benefit of focusing on a speaker or event of interest while rejecting ambient background noise. These attributes make this innovation ideal for addressing an emerging need of high volume consumer communication device manufactures who are looking for acoustic sensing innovations with the unique combination of high performance + low manufacturing cost. The objective of this Phase II innovation is to continue prototyping efforts from Phase I to the point of pilot scale manufacture. This effort will entail finite element modeling and design optimization of the new device structure, fabrication of 2nd generation prototypes, and experimentation in collaboration with customers from several different microphone sectors including hearing aids and cellular phones. The broader impact/commercial potential of this project is based on an enabling capability: the introduction of advanced audio features (e.g. directionality and high fidelity) into a suite of consumer communication devices. The primary customer focus for this innovation is high volume consumer communication device manufacturers. New applications on their horizon demand improvements in microphone component performance. There are presently several commercial suppliers of MEMS microphones. All use variations of a traditional microphone architecture which has proven incapable of addressing high SNR applications. Additional markets and applications for this innovation include acoustic instrumentation, performance audio, military and defense, intelligence gathering, speech recognition (e.g. in laptop computers), and hearing aids. Addressing hearing aid markets will have a societal impact as well, as patient satisfaction with hearing aid devices is presently very low. Innovations at the microphone and signal processing level have the potential to improve this greatly. The innovation is also expected to have other audiological applications including use in hearing health monitoring systems based on otoacoustic principles. Clinical tools and instruments based on this innovation will serve to enhance scientific and technological understanding in many fields of acoustics.