Fem Modeling Rayleigh Wave Sensors Based on GO/SiO2/128° YX-LiNbO3 Structures

Abstract

3D-finite element method (3D-FEM) is used to investigate the characteristics of Rayleigh wave devices based on GO(Graphene Oxide)/SiO2/IDT(inter-digital transducer)/128° YX-LiNbO3 structures, including the phase velocity vp, electromechanical coupling coefficient k², and gas sensing properties. The results show that the GO layersimprove the characteristics of the Rayleigh wave devices, that is, vp andk² are increased by the introduction of GO films. And thek²of 9.32% associated with phase velocity of 4517m/s have obtained as hs/λ=0.01 and hGO=0.5μm, which are higher than that of GO free Rayleigh wave device. Meanwhile, the gas sensing sensitivity of theRayleigh wave sensor is also enhanced by GO layers. Therefore, GO is an ideal material for constructing SAW sensors for widespread applications.