Fabrication of high-quality PZT-based piezoelectric microphone

This paper proposes a novel lead-zirconate-titanate (PZT)-based structure used for the integrated microphone. The performance of the PZT thin films and the devices were improved due to adoption of the lead-titanate (PT) layer as the seeding layer. The PZT-based piezoelectric microphones with conductor-piezoelectric-conductor sandwich structure were fabricated. The size of the finished microphone ranged from 600/spl times/600 /spl mu/ m/sup 2/ to 1000/spl times/1000 /spl mu/ m/sup 2/. A high sensitivity of 38 mV/Pa can be obtained. This quality was prominent in the existed microphones. The frequency response of the microphone was very flat in the audio frequency range. The novel piezoelectric microphones should be very promising for acoustic applications.