Surface acoustic wave devices for gas identification and monitoring applications

摘要

Surface acoustic wave (SAW) sensors offer a direct, sensitive method for monitoring the chemical and physical properties of gases. These devices are integrated into an oscillator circuit such that the Rayleigh wave propagation on the surface of the crystal is the mechanism by which deviations on the surface can be monitored. Mass loading and changes of elastic properties of the device surface due to physiochemical interactions affect how the energy propagates along the surface and may be monitored via frequency shifts of an oscillator.