声表面波介质表面受力条件下的波速变化研究

Velocity variation of surface acoustic wave under force applied on the propagation surface

摘要: 为了计算力负载直接作用在声表面波传播表面时波速的变化特性,通过有效材料系数将负载引入,并用广义Green函数计算声速,得到了数值计算的结果,并用声表面波谐振器进行了实验。实验结果表明,将力负载直接加载在声表面波的传播表面时,波速变化量和力负载大小近似为线性关系,该加载方式下,实验中声表面波谐振器的谐振频率对外加质量负载有较高的灵敏度,可达1900Hz/g。

Abstract: The velocity variation under a force directly loaded on the propagation surface of Surface Acoustic Wave (SAW) is analyzed. Effective material coefficients are utilized to involve the force loading and the general Green's Function is used to calculate the velocity of SAW. In experiments, force is applied on the surfaces of SAW resonators, and the experimental results are consistent with the numerical calculations. The results also show that the velocity variation of SAW is proportional to the load, and the resonance frequency shift of SAW resonator has a high sensitivity to mass load applied on the propagation surface(about 1900 Hz/g).