Analysis of Rayleigh wave radiations from leaky SAW resonators

The Rayleigh wave radiations from leaky surface acoustic wave (SAW) resonators on around 42° Y-cut LiTaO₃ substrates are known as one of acoustic loss mechanisms. This paper analyzes and characterizes the Rayleigh wave radiations and develops the analytical model for the radiations. First, the finite element method (FEM) analyses and optical probe measurements reveal that the scattering of leaky SAW at the gap between interdigital transducer (IDT) and dummy electrodes generates the Rayleigh wave radiations. Based on the result, the simple and fast analytical model using the point sources is developed to simulate the Rayleigh wave radiations. The model precisely simulates the measurement patterns of radiations about 1,000 times faster than the FEM.