Design of IF two-track filters using IDT/(100) AlN/diamond structure

Abstract

Propagation characteristics of surface acoustic waves (SAWs) in IDT/(100) AlN/diamond structures are analyzed in this study using the finite element method (FEM). The extracted coupling-of-mode (COM) parameters are employed to calculate the frequency responses of two-track SAW filters using the transmission matrix method. To enhance the sideband suppression, Chebyshev function is adopted to modify the reflectivity distributions of reflectors, which can be realized using width-modulated reflectors. The copper electrode is used to retain a sufficiently high reflectivity. Simulation results show that a two-track SAW filter applicable for the CDMA system can be tailored using IDT/(100) AlN/diamond structures.