Seminary : Flush Mounted Piezoelectric Microphones for Flight Testing

To understand and mitigate the impact of noise sources on an aircraft, aeroacoustic researchers are in need of a high performance, low cost microphones to address the increasing noise restrictions on commercial aircraft. Existing commercial sensors, even with their relatively high cost, in some cases constrain the quality and type of measurement that may be achieved. This talk presents the design, fabrication and calibration developments of the first truly flush-mount piezoelectric microelectromechanical (MEMS) dynamic pressure sensor with associated packaging for aircraft fuselage arrays. Through-silicon-vias (TSVs) are incorporated into the fabrication of the sensor to eliminate front-side wire bonds and enable an overall flush surface for the packaged sensor that minimizes flow disturbance. The developed packaging method for the sensor demonstrates an overall flushness to within 10 μm, showing substantial improvement from any previously reported efforts.