Experimental and theoretical analysis of silicon-based piezoelectric transducers for ultrasound imaging

The development of new Micromachined Ultrasound Transducers (MUT) for medical imaging or Non Destructive Evaluation (NDE) has been allowed by the vulgarization of MicroElectroMechanical Systems (MEMS) technologies. The possibility to massively produce very high quality transducers (high sensitivity, large SIR, good dynamics) directly integrated on silicon substrates with a high throughput represents a significant advance in acoustic imaging. The proposed work consists in the analysis of piezoelectric MUT to characterize their main properties (coupling coefficient, resonant frequencies, acoustic impedance) from both theoretical and experimental point of view. Computation using 3D finite element analysis has been achieved and compared to experiments performed on large scale PZT/Si transducers. Electrical responses have been measured together the distribution of dynamical displacements using an optical interferometer at resonant frequencies to check the validity of the theoretical analysis.