Simulation and analysis of two structures from SAW gas sensor based MEMS gas sensor

In this paper two structures of Surface Acoustic Wave (SAW) sensor: classical single electrode Interdigited Transducer (IDT) and standard double split electrodeInterdigited Transducer (IDT), based Micro Electro Mechanical Systems (MEMS) gas sensor are simulated by using comsol multi-physics software based on Finite Element Method (FEM). The shift in resonance frequency of the SAW sensor for both structures was determined and the effect of changing the width,position and thickness of the electrodes as well as the thickness of the sensing layer and substrate height on the shift in resonancefrequency, electrical potential and total displacement at resonance frequency has been studied and in order to enhancing sensitivity and shift in resonant frequency, a new model is presented. But have maintained the same wavelength to allow for easier comparisons.

Keywords:

surface acoustic wave , interdigited transducer , MEMS , finite element method , piezoelectric