Analysis of Surface Acoustic Waves Obliquely Propagating under Metallic Gratings with Finite Thickness

Abstract

In this paper we propose a method of analysing surface acoustic waves (SAWs) propagating obliquely under a metallic grating with finite thickness. The discrete Green function originally developed for SAWs longitudinally propagating under the metallic grating is modified, and applied to the characterisation of obliquely propagating SAWs. The method is applied to the analysis of Rayleigh SAWs obliquely propagating on 128° Y X-LiNbO3 (128-LN), and the result is shown to be in good agreement with experiments. Leaky SAWs obliquely propagating on 36° Y X-LiTaO3 (36-LT) are also analysed and compared with the result obtained for 128-LN.

Fast FEM/BEM simulation of SAW devices via asymptotic waveform evaluation

“…From this condition the vector C (m) φ is easily determined. The mechanical contribution in (8) can be eliminated by inserting (10), and the resulting system solved for C (n) Q . The total electrical charge Q 0 under the electrode is computed by integration of the charge density.…”

Fast FEM/BEM Simulation of SAW Devices Via Asymptotic Waveform Evaluation

“…From this condition the vector C (m) φ is easily determined. The mechanical contribution in (8) can be eliminated by inserting (10), and the resulting system solved for C (n) Q . The total electrical charge Q 0 under the electrode is computed by integration of the charge density.…”

“…Ventura et al [8] have especially deeply optimized the FEM/BEM method by analytically integrating the asymptotic contributions of the spectral surface Green's function. It also has been used as a mathematical tool for the identification of the modes guided by the interface between a piezoelectric substrate and high aspect ratio metallic electrodes [9], and for the analysis of surface waves propagating obliquely in IDTs [10], [11].…”

Simulation of Surface Acoustic Wave Devices

“…[52][53][54][55][56][57][58] Again the use of behavior models is essential, and simplified two-dimensional analysis is applied for the extraction of simulation parameters.…”