Numerical Optimization of Structures SAW Gas Sensors

This paper presents the results of the analysis of surface acoustic waves sensor equivalent model. They were the sensor response of the surface acoustic waves sensor in the steady state gas: $H_2$, $CO_2$, $NO_2$, $NH_3$, $C_nH_m$, $CO$. Thin layer of $WO_3$ has been used as a sensor layer. Impedance replacement of sensor layer, taking into account the profile of the concentration of gas molecules in the layer, has been implemented into the equation of Ingebrigtsen, which enabled us to obtain analytical expressions for the relative changes in surface wave velocity in the steady state. The results of the analysis show that there is an optimum thickness of layer sensor for which an acoustoelectric effect (change in the acoustic wave velocity) is the highest.