Simulations of acoustic waves bandgaps in a surface of silicon with a periodic hole structure in a thin nickel film

Abstract

We have performed simulations of dispersion relations for surface acoustic waves in two-dimensional phononic crystal by the finite elements method (FEM) and by the plane wave method (PWM). Considered medium is a thin nickel layer on a silicon single crystal (001) surface. The nickel film is decorated with cylindrical holes of the depth equal to the nickel film thickness arranged in a square lattice. We have obtained full bandgaps for the surface waves propagating in the medium of particular range of filling factor and layer thickness. The width of the bandgap had reached over 500[MHz] for the sample of the lattice constant 500[nm] and is sufficient for experimental design.

Acoustic band gaps due to diffraction modes in two-dimensional phononic crystals

“…The acoustic wave propagation in the 2D PCs was simulated using FEM with the acoustic module of COMSOL Multiphysics software. 20) The calculated frequency ranges were from 300 to 1300 kHz with 2 kHz intervals. The normal component of the velocity of the water particles is zero on the walls of the rods because reflecting boundary conditions were applied at the interfaces between the stainless-steel rods and water.…”

Band structure analysis of leaky Bloch waves in 2D phononic crystal plates

“…[9] as well as Finite Element (FEM)-based absorbing regions [10,11,12] and Perfectly Matched Layers [13,14], while the so-called Plane Wave Expansion (PWE) method has been used in [15,16,17].…”