FEM Simulation Analysis of AlN/SiO 2 /Si Multilayer Structure and Effect of IDT Configuration on SAW Propagation Modes and Characteristics

In this paper, Finite Element Method (FEM) simulation analysis of a CMOS compatible AlN/SiO 2/ Si SAW device is performed to investigate the Surface Acoustic Wave (SAW) modes and their propagation characteristics. A SAW resonator was simulated based on piezoelectric thin film of Aluminum Nitride (AlN) on passivated silicon (SiO 2 /Si) substrate. The SAW properties of AlN film on SiO 2 /Si were analyzed with two composite structures: (IDT)/AlN/SiO 2 /Si and AlN/(IDT)/SiO 2 /Si, and they revealed some good SAW properties. The maximum value of $\pmb{k}^{\mathit{2}}$ is almost same for both SAW modes with both IDT configurations, but on different values of $\pmb{t}_{\pmb{AlN}}/\lambda$ and $\pmb{t}_{\pmb{SiO2}}/\lambda$. The results stipulate a theoretical basis for further application on high frequency SAW devices. The proposed SAW device based on AlN/SiO 2 /Si structure have potential applications in integrated sensing applications.