Application of hierarchical cascading technique to finite element method simulation in bulk acoustic wave devices

Abstract

In this paper, we propose the use of the hierarchical cascading technique (HCT) for the finite element method (FEM) analysis of bulk acoustic wave (BAW) devices. First, the implementation of this technique is presented for the FEM analysis of BAW devices. It is shown that the traveling-wave excitation sources proposed by the authors are fully compatible with the HCT. Furthermore, a HCT-based absorbing mechanism is also proposed to replace the perfectly matched layer (PML). Finally, it is demonstrated how the technique is much more efficient in terms of memory consumption and execution time than the full FEM analysis.

From Microwave Acoustic Filters to Millimeter-Wave Operation and New Applications

“…Furthermore, other advantages exists: (a) capability to reuse intermediate results [43] to investigate variation of device characteristics with some design parameters, by running parameter scans, (b) capability to simulate semi-infinite structures [44], and (c) realization of damping mechanisms [43], [44], [45] for cases where PML does not work properly.…”

Perturbation analysis of nonlinear responses caused by transverse modes in AlN FBAR based on 2D scalar wave model

“…The surrounding layers are designed as follows: first, Γ is calculated as a function of β and the incident angle θ to the side edge using periodic 2D FEM 22) in combination with the traveling wave excitation 23) and the hierarchical cascading technique. 24) Then b k , c k , and the number of layers are determined by the fitting.…”

Spurious-free thickness-shear bulk acoustic resonators on lithium niobate using standard and broadband piston mode designs

“…5(a), where one frame (bump) is placed on the top electrode edge to adjust the phase of the reflection coefficient G ¢ y at the incident edge of the frame. The traveling wave excitation source 15) is applied for the frequency-domain scattering analysis using the 2D FEM, 16) and the hierarchical cascading technique 17) is applied for the calculation acceleration.…”

“…Next, frames are designed systematically for the standard piston mode operation. Reflection characteristics are analyzed by the 2D FEM in combination with the traveling wave excitation source 15,16) and the hierarchical cascading technique, 17) while the admittance is obtained by the standard 2D FEM. Then, it is shown how the frame design influences the resonator performance.…”