Sound is characterized by rapidly oscillating pressure fluctuations in air. Microphones, therefore, are similar in construction to regular pressure sensors. Microphones consist of both a compliant diaphragm that deforms under sound pressure and a system for detecting the diaphragm’s vibrations. Traditional microphones detect this vibration electrically. Silicon Audio is applying its core competencies in MEMS, optics, and piezoelectric materials to realize unconventional high-SNR (signal-to-noise ratio) MEMS microphones with unprecedented performance and features.
Silicon Audio takes a fundamentally different approach to building omnidirectional, high-SNR MEMS microphones. By using the interference of light waves to detect the vibration of a diaphragm fabricated on silicon, we break through the performance barriers imposed by traditional detection principles. Our innovation combines mechanical elements fabricated on silicon (i.e ., MEMS technology) with semiconductor lasers and CMOS electronics to realize a microphone rivaled in sensitivity only by microphones 100x larger in size and 100x more expensive to produce.
The majority of MEMS microphones mimic their large-scale omnidirectional counterparts, but Silicon Audio is pursuing an alternative approach: microphones that have an inherently directional response to sound. We leverage our expertise with piezoelectric microfabrication to mimic hearing organs found in nature and to create directional microphones with high SNR. These ultra-small MEMS microphones offer advantages for applications such as hearing assistive devices and consumer electronics.