Multi-channel thin film piezoelectric acoustic transducer for cochlear implant applications

This paper presents a multi-channel piezoelectric acoustic transducer that is working within the audible frequency band (250- 5500 Hz). The transducer consists of eight cantilevers with thin film PLD-PZT piezoelectric layers. The transducer is well suited to be implanted in middle ear cavity with an active volume of 5×5×0.6 mm 3 and mass of 4.8 mg excluding the test frame. Finite Element Method (FEM) is used for modelling cantilever resonance frequencies and piezoelectric outputs. This model and shaker-table experiments are in good agreement on the frequency (97%) and output voltage (89%) values. Transducer can generate up to 139.36 mV pp under 0.1 g excitation at 316 Hz, which is the highest reported output voltage from a piezoelectric acoustic sensor to the best of our knowledge