SiO2/IDT/AlN/Diamond多层结构中声表面波传输特性的有限元分析

基于COMSOL软件对SiO2/IDT/AlN/Diamond多层结构中声表面波(surface acoustic wave,SAW)传输特性进行有限元(finite element method,FEM)分析.深入分析了多层结构中声波的色散特性,直观地展现了表面波向漏表面波的转化过程,研究了Al电极层厚度和SiO2缓冲层厚度对声表面波的影响.基于微加工工艺研制出一系列不同结构的声表面波谐振器,并对其频率响应特性进行了测试.测试结果与仿真结果基本一致,其中,1阶模式的声表面波表现出较好的应用潜力,可用于声表面波滤波器的研制.

FEM investigation of surface acoustic waves propagating in SiO2/IDT/AlN/Diamond multilayered structure

In this paper, the finite element method(FEM) simulation based on COMSOL software is applied to investigate the SAWs propagating in the SiO₂/IDT/AlN/Diamond multilayered structure. The dispersion properties are researched, the conversion of SAW to PSAW is visually presented, and the influences of the Al electrode thickness and SiO₂ buffer layer thickness to the SAWs are investigated. At last, a series of SAW resonators based on the SiO₂/IDT/AlN/Diamond multilayered structure are fabricated by micromachining, and their frequency responses are detected. The experimental results are found to be mainly consistent with the simulated ones. And the 1^st mode SAW in the SiO₂/IDT/AlN/Diamond multilayered structure is believed to have the great potential in the further SAW device applications.