Design of Love wave sensor devices for the operation in liquid environments

Abstract

Love wave sensors are highly sensitive microacoustic devices, which are well suited for liquid sensing applications. The successful utilization of Love wave devices thereby requires proper shielding to avoid unwanted electric interaction of the liquid with the wave and the transducers. In this contribution we describe the effects of this electric interaction and the proper design of a shield to prevent it. Analysis methods illustrating the impact of the interaction and providing rules for the optimized design of the proposed shield are presented. Finally we show experimental results for devices that have been fabricated according to these design rules.