Prototyping of a High Frequency Phased Array Ultrasound Transducer on a Piezoelectric Thick Film

Abstract

A process including virtual prototyping of a high frequency phased array ultrasound transducer on a piezoelectric thick film using a finite element method (FEM) is shown. Generated FEM models were based on PMN-PT (Pb(Mg1/3Nb2/3)O3-PbTiO3) thick films, made by sol-gel technique, with the thickness vibrational mode resonant frequency of each film being close to 28.5MHz. Ultrasound transducers with such characteristics, due to their size and high frequency, are suitable for use in small medical diagnostic tools intended for use in delicate and sensitive areas (for example in ophthalmology and dermatology). With respect to their size, the transducers should retain very good focusing, beam steering and other advantages that phased array layout offers. To ensure an optimal performance of the phased array ultrasound transducer on such a piezoelectric thick film, several electrode patterns were used and tested in FEM simulations with the end goal of getting best performance from the PMN-PT thick films. A 64-element configuration was shown to be a promising technological solution for ophthalmological ultrasound diagnostics.