Application of Surface Acoustic Waves in Gas Sensors

This textbook offers the most important issues related to the application of surface acoustic waves (SAW) in gas sensors. The essence of operation, general theoretical models, research methodology, bi-layer and light-activated sensor structures are presented in an understandable way. The original results of the sensor properties studies of selected single, bilayered structures, as well as prototype multi-layer structures and for the first time, a detailed theoretical description of the acoustoelectrical effect for bilayer sensor structures were presented. Most attention was paid to semiconductor-metal bilayer structures, such as phthalocyanine-palladium or tungsten oxide-palladium, as they are the most promising in terms of practical applications in SAW hydrogen sensors. The prospects of applications and further research taking into account the latest solutions based on light-activated photoconductive polymer structures are also indicated.