The theoretical studies on acoustoelectrical (AE) sensitivity in SAW gas sensors are presented. The analysis was based on normalized parameter ξ=σs/v0Cs(where: σs-is the film's electrical surface conductivity, v0-SAW velocity, Cs-sum of the substrate's and environment's electrical permittivities) which determines the value of AE sensitivity. The electrical surface conductivities in the bi-layer structure are correlated by the σs1= x σs2dependence. The investigations revealed that for single and bi-layer sensor structures the maximum value of AE sensitivity is obtained for ξmax= ∼0.6. For bi-layer structures this sensitivity is lower. However we also found the positions of the maximum values in a function of x parameter dependent on different values of normalized conductivity of the second film.
Jakubik, W., Powroźnik, P., Wrotniak, J., Krzywiecki, M., & Hejczyk, T. (2015). Theoretical analysis of acoustoelectrical sensitivity in SAW gas sensors. In Procedia Engineering (Vol. 120, pp. 1261–1264). Elsevier Ltd. https://doi.org/10.1016/j.proeng.2015.08.844