首先从理论上阐述了声表面波(SAW)谐振器传播属性的有限元分析(FEA)法;然后利用ANSYS软件,对ST切石英晶片的SAW谐振器进行模态分析和谐响应分析;最后处理仿真结果并得到结论:通过合成表面节点横向和纵向的模态位移得出SAw中质点的运动轨迹是椭圆,通过模态频率和对应的波长算出SAW在ST切石英晶片中的传播速度,通过分析纵向节点模态位移得出SAW的能量集中在距表面2个波长深度的范围内,通过幅频特性图得出谐振器在SAW频率处具有最大的频率响应。这些结论与理论基本一致,为设计SAW器件和研究SAW传感器提供了仿真依据。
Firstly, the finite element analysis(FEA) method of the propagation properties of SAW resonator has been presented theoretically. Secondly, the modal and harmonic analyses of SAW resonator constructed with ST-cut quartz slice have been performed by utilizing ANSYS software. Lastly, the simulation result data have been processed and come to the following conclusion: that the motion track of each particle in the SAW is an ellipse has been obtained by combining the transverse modal displacement and longitudinal modal displacement of each surface node, the velocity of SAW propagating on the ST-cut quartz slice has been calculated by the model frequency and relevant wavelength, that the SAW energy is concentrated within the depth of two waves from surface has been obtained by analyzing the node displacement variation with depth, that the resonator has largest response at the SAW frequency has been acquired from the amplitude-frequency characteristic graph. These conclusions are mainly identical to the theoretical values, which offer the simulation basis for designing SAW device and studying the SAW sensor.