Development of a piston type condenser microphone for reconfigurable acoustic arrays

Abstract:
This work presents an innovative method to achieve piston type capacitive silicon microphones suitable for reconfigurable acoustic arrays. The primary advantage of silicon based microphones is the high degree of miniaturization achievable, which together with the reproducibility of the transducer characteristic provides great compatibility with batch production at low cost. Piston type capacitive microphones offer better electro-acoustical transduction than membrane type ones, and can be easily packaged as there is not need for a static pressure balancing. Their ability to be co-integrated with preamplifier circuitry reduces parasitic capacitances and further enhances microphone performance, becoming a very appealing solution for complex audio applications where weight, compactness and reliability are crucial.