In MEMS realization of high frequency ultrasonic array transducer, electrical impedance matching may become difficult for the reason of the miniaturization of the piezo-array elements. In this study, the electrical impedance of the array elements is estimated first by using KLM model, and then calculated by using finite elements method (FEM), in the case of a LiNbO3 based 30MHz array transducer. The impedance frequency behavior is related both to the eigen-resonance modes and the electrode driven modes with the free mechanical boundary condition of the element and to the coupling of these modes to the array structure when the element being integrated as the transducer. The array transducer properties and performances such as lateral modes, crosstalk, sensibility and bandwidth, field radiation, focusing/steering are also simulated and analyzed.
Financed by the National Centre for Research and Development under grant No. SP/I/1/77065/10 by the strategic scientific research and experimental development program:
SYNAT - “Interdisciplinary System for Interactive Scientific and Scientific-Technical Information”.