Highly sensitive SAW sensors

This paper presents experimental data on the performance of some types of SAW sensors like, biosensor, gas sensor and pressure sensors. It is shown that such parameter, as sensitivity is determined by kind of piezocrystal cut and direction of SAW propagation as well as by the construction of sensor, method of treatment of signal, properties of covering film adsorption. It is shown that such devices have a high sensitivity to the liquid temperature, gas concentration and pressure, respectively. Typical data of sensitivity of our sensor ate as follows. Biosensor has possibility to measure relative velocity change of about 5.7/spl middot/10/sup -8/, gas sensor has the sensitivity of about 100/spl divide/1000 Hz/ppm, at last different pressure sensors have sensitivity of the order of 4.0 Hz/Pa for low pressure and 0.02 Hz/Pa for the high one. The general properties of measurement are determined on the features of frequency control element.<
>