不同切向衬底的声表面波传播特性仿真

声表面波(Surface Acoustic Wave,SAW)是在固体表面传播的一种弹性波。SAW谐振器是传播和处理SAW的一种器件,其对SAW可进行滤波、延迟等处理。压电单晶是制作SAW谐振器的重要材料,其通常具有各项异性。基于同一种压电材料的不同切向制作的SAW谐振器,其SAW的传播特性、温度特性和应变特性等有较大差异。本文基于Bond矩阵旋转的方法,对硅酸镓镧(La3Ga5SiO14,LGS)压电单晶在(0°,138.5°,26.6°)切向上的弹性系数矩阵、介电常数矩阵和耦合矩阵进行旋转变换计算。并利用COMSOL软件仿真LGS单晶不同切向上的SAW的传播特性。仿真结果与已有的实验结论有较好的符合度,此方法可用于指导SAW谐振器的设计。

Surface Acoustic Wave(SAW)is an elastic wave that propagates on a solid surface.SAW resonator is a device that propagates and processes SAW,which can perform processing such as filtering and delaying SAW.Piezoelectric single crystals are important materials for making SAW resonators,which usually have anisotropy.SAW resonators made based on different cuts of the same piezoelectric material have large differences in SAW propagation characteristics,temperature characteristics,and strain characteristics.In this paper,based on the Bond matrix rotation method,the elastic coefficient matrix,dielectric constant matrix,and coupling matrix of the La3Ga5SiO14(LGS)piezoelectric single crystal in the(0°,138.5°,ψ)cut direction are rotated and calculated.The COMSOL software is used to simulate the propagation characteristics of SAW in different cuts directions of LGS single crystals.The simulation results agree well with the existing experimental conclusions.This method can be used to guide the design of SAW resonators.