Finite‐element analysis of SAW reflection from a metallic grating with an arbitrary angle of incidence

Abstract

AbstractWith a view to developing a method enabling accurate derivation of the reflection characteristics for an oblique incidence of the surface acoustic wave (SAW) into a metallic grating which is a fundamental constituent element of an SAW device, an analysis method is formulated based on the finite‐element method (FEM). The FEM can easily be applied to an anisotropic and piezo‐electric substrate. It is possible to carry out an analysis taking into account the electrical perturbation, mechanical perturbation, and the energy storage effect by a nonradiating bulk wave at the reflection end.In this paper, from the information on the stopband computed by the FEM, the amount of reflection per reflecting strip in the reflector and the shift of the center frequency of the stopband are computed. These quantities are actually computed for gratings on a Bi12GeO20 substrate and an ST‐cut quartz substrate so that the validity and usefulness of the present analysis method are presented.