Acoustic sensors based on surface-localized HPSWs for measurements in liquids

Abstract

Acoustic wave probes based on horizontally polarized shear waves (HPSWs) in quartz plates are presented. These probes can be applied as physical or chemical sensors for measurements in liquids and to characterize thin solid films mechanically. An appropriate and comprehensive simulation tool has been developed and is used to work out the specific advantages of the proposed probing system, to interpret the experimental data and to optimize the probing devices for special measurement purposes. The use of additional coatings of known consistency is introduced, which leads to an enhanced sensitivity and a reduction of cross-sensitivities, in particular for surface-localized HPSWs in quartz, which have not yet been the subject of sensor research. Theoretical and experimental results confirm the huge potential of HPSW devices for sensing applications in liquids.