Properties of sensors based on shear-horizontal surface acoustic waves in LiTaO3/SiO2 and quartz/SiO2 structures

Acoustic wave devices based on waveguide modes with shear-horizontal polari zation, i.e., Love modes, are very promising for sensor application, especi ally in liquid environments. They can be used for the determination of liqu id density and viscosity as well as for chemical sensors. Up to now, severa l systems have been reported based on standard ST quartz. Those devices lac k temperature stability which is essential for field application, Thus, tem perature-compensated systems based on different Y-rotated quartz and lithiu m tantalate (LiTaO3) plates with SiO2 guiding layers have been investigated . Temperature behavior as well as relevant acoustic properties were conside red. Furthermore, experimentally determined data for device sensitivity are compared with theoretical predictions from numerical calculations.