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

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).