Finite element analysis of lateral field excited thickness shear mode film bulk acoustic resonator

Abstract

Purpose

This paper aims to propose a new model to study the relationship between the acoustic properties of the thickness shear mode (TSM) in lateral field excited (LFE) film bulk acoustic wave resonator (FBAR) and the gap distance of the surface electrodes.

Design/methodology/approach

In the finite element analysis, harmonic and modal analyses are performed to obtain the admittance spectrum and determine the mechanical vibration mode. The results are used to modify the ideal model used in the theoretical calculation.

Findings

In the case of LFE FBAR, the acoustic velocity and electromechanical coupling coefficient (K2) of the TSM decreases as the gap distance decreases and there is a compromise between the exciting effectiveness and the acoustic properties.

Originality/value

The paper proposes a new method to study the dependences of the acoustic properties of the lateral field excited FBAR on the gap distances of the surface electrodes through the extraction of the static capacitance based on the finite element simulation results.

Citation

Zhou, C., Yang, Y. and Ren, T. (2012), "Finite element analysis of lateral field excited thickness shear mode film bulk acoustic resonator", COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, Vol. 31 No. 6, pp. 1892-1900. https://doi.org/10.1108/03321641211267173