A new capacitive type MEMS microphone

A new capacitive type of MEMS microphone is presented. In contrast to existing technologies which are highly specialized for this particular type of application, our approach is based on a standard process and layer system which has been in use for more than a decade now for the manufacturing of inertial sensors. For signal conversion, a mixed-signal ASIC with digital sampling of the microphone capacitance is used. The MEMS microphone yields high signal-to-noise performance (58 dB) after mounting it in a standard LGA-type package. It is well-suited for a wide range of potential applications and demonstrates the universal scope of the used process technology.