Lamb wave transducers built on periodically poled Z-cut LiNbO3 wafers

Abstract

In this paper, the development of piezoelectric transducers based on periodically poled ferroelectric domains is investigated. Optical quality Z-cut LiNbO3 wafers have been used for the fabrication of test devices operating in the range of 10–100MHz. The fabrication process is detailed and the characterization results are reported. A very good agreement between theoretical predictions achieved by periodic finite element analysis and experiments is observed, allowing for a precise identification of the excited modes. Elliptically polarized modes as well as quasipure longitudinal waves are pointed out. The robustness of the devices to lapping and polishing operations has also been tested. The possible utilizations of such transducers are discussed to conclude the paper.