Tung Manh¹, Anh Tuan. T. Nguyen¹, Lars Hoff¹, Tonni F. Johansen<sup>2

1</sup>Faculty of Science and Engineering, Vestfold University College, Vestfold, Norway
²Department of Circulation and Medical Imaging, University of Science and Technology, Trondheim, Norway

Proceedings of the 33rd Scandinavian Symposium on Physical Acoustics

Abstract

We present a new design of high frequency ultrasound transducers using thick-film PZT on Silicon for medical application. Air is used as backing material for the PZT film, and the ultrasound pulses are transmitted through the silicon substrate. The silicon substrate is micromachined to build acoustic matching layers to optimize the acoustic coupling between the active PZT layer and the tissue, and achieve a large bandwidth. The number of matching layers in the design could be either two or three, depending on the fabrication methods to make the PZT thick-film, i.e. tape casting or screen printing. A prototype of two matching layers for a 10MHz transducer has been made. 1D analytical calculations and FEM simulations show that the proposed design will have a 3 dB bandwidth ranging from 7.5 MHz to 13 MHz, or 55% bandwidth at center frequency of 10 MHz. Acoustic measurement is ongoing.