Other Surface-Acoustic-Wave Based Instruments

Abstract

There is a variety of sensing instruments making use of acoustic waves (often shear waves) near interfaces. Among the concepts shared between the QCM and these instruments are the mass sensitivity and the acoustic reflectivity as a central intermediate parameter. The kHz resonators measure viscoelastic parameters at frequencies more relevant to most applications than MHz frequencies. On the other hand, they are less sensitive. Smaller resonators operating at higher frequencies tend to have better mass-sensitivity. Shear-Wave ReflectometersThe shear-wave reflectometer dates from the time when acoustic sensing started. It has seen numerous developments and extensions since then. Figure 15