Bulk Wave Excitation From Finite Length Saw Transducers Including Massloading

A analysis of bulk wave generation from finite length transducers on YZ-LiNbO3 is presented. The effect of the metallic electrodes is taken into account using the Finite Element Method. The substrate is modeled using both analytical and numerical means. The simulation results suggest that thick electrodes (gold or aluminum) increase the electrical coupling of a uniform SAW transducer to the shear vertical bulk wave at approximately twice the SAW center frequency. Experimental data in the literature appears to support this assertion