Analysis and optimization of Love wave liquid sensors

摘要

Love wave sensors are highly sensitive microacoustic devices,nwhich are well suited for liquid sensing applications thanks to thenshear polarization of the wave. The sensing mechanism thereby relies onnthe mechanical (or acoustic) interaction of the device with the liquid.nThe successful utilization of Love wave devices for this purposenrequires proper shielding to avoid unwanted electric interaction of thenliquid with the wave and the transducers. In this work we describe theneffects of this electric interaction and the proper design of a shieldnto prevent it. We present analysis methods, which illustrate the impactnof the interaction and which help to obtain an optimized design of thenproposed shield. We also present experimental results for devices thatnhave been fabricated according to these design rules