Design of piezoelectric cantilever microphone and its MEMS-acoustical circuit for hearing aid devices

A micromachined piezoelectric cantilever transducer, which works as a microphone has been designed. The 1800 /spl times/ 1800 /spl times/ 2.9/spl mu/m/sup 3/ cantilever has a lead zirconate titanate (PZT) piezoelectric thin film sandwiched between two aluminum electrodes on a supporting layer of silicon nitride. The static analysis of piezoelectric cantilever is typically performed, which describes the deflection of a generic m-layer piezoelectric multimorph, and acoustic modeling of the microphone has been described. The maximum deflection at the tip of the cantilever is 22/spl mu/m, and the maximum difference output voltage between two electrodes is 0.1mV.