#MEMS: "Piezoelectric MEMS mics Seem Destined to Take Over"

Piezoelectric MEMS microphones have already chalked up 70 dB signal-to-noise rations (SNRs) and are on their way to 80 dB, which is virtually unattainable by the conventional capacitive MEMS mics that everybody else makes: R. Colin Johnson @ NextGenLog

Instead of a traditional round diaphragm like capacitive microphones use (right) piezoelectric microphones use a square block of piezoelectric material (aluminum nitride, green) divided into four triangles (along the X from corner to corner) which stretch and contract--but never touch--thus creating an ultra low-noise signal picked up by the metal (yellow and gold) electrodes.


FURTHER READING