Parametric Studies of Multilayer Structure Surface Acoustic Wave Resonators

Abstract

Multilayer structure is a potential way to obtain high-performance surface acoustic wave (SAW) devices. In applications, the combination of high propagation velocity and strong piezoelectric coupling is required for acoustic modes applied to wideband high-frequency SAW devices. To meet the requirements, an optimal orientation (90° 90° 45°) LiNbO3 is investigated by a rigorous numerical simulation of the Green’s functions of LLSAWs and an accurate extraction of the propagation losses. In addition, the numerical simulation method and finite element method (FEM) are applied to investigate how parameters of high acoustic impedance (HAI) materials affect the propagation and the resonance characteristics of SAW resonators. The results demonstrate that HAI materials with proper density, rigidity, acoustic impedance and thickness could improve the performance of the SAW devices.