Modelling and simulation of SAW delay line sensors with COMSOL Multiphysics

This study concerns 2D and 3D Finite Element Method (FEM) simulation of surface acoustic wave (SAW) sensors using COMSOL Multiphysics software. SAW device has been designed on piezoelectric substrate; 36° rot lithium tantalate (LiTaO3). Simulations were made on well-known structure to ensure the concordance between 2D and 3D models, and to define a 2D one that can account for and predict the electrical behaviour of SAW transducers for the future optimizations. The results show good agreement between numerical simulation and experimental S21 spectra. Accordingly, we can use the 2D built model for simulations intended to optimize the structure of devices, mainly for increasing their sensitivity.