Title :
Modelling of 2-D lateral modes in solidly-mounted BAW resonators
Author :
Meltaus, Johanna ; Pensala, Tuomas ; Kokkonen, Kimmo
Author_Institution :
VTT Tech. Res. Centre of Finland, Espoo
Abstract :
Lateral resonances occurring in bulk acoustic wave resonators contribute to the device operation, e.g., by creating spurious electrical responses. Predicting lateral effects in two dimensions typically requires computationally heavy 3-D finite element modelling. Here, dispersion characteristics calculated using a 1-D transfer matrix model are used in a finite-element software to model lateral resonance modes of solidly-mounted bulk acoustic wave resonators. Based on the resulting spectrum of 2-D eigenmodes, electrical frequency response as well as mechanical displacement is then calculated using mode superposition. Resonators with elliptic and rectangular shapes are studied. Simulated results for ellipses are compared to measured electrical frequency response and mechanical displacement. Simulations are found to agree with measured data. Dependence of electrical spurious responses on resonator shape and eigenmode spectrum is studied.
Keywords :
acoustic dispersion; acoustic resonance; acoustic resonators; bulk acoustic wave devices; eigenvalues and eigenfunctions; finite element analysis; 1D transfer matrix model; 2D eigenmode spectrum; 2D lateral resonance mode; 3D finite element model; bulk acoustic wave resonator; dispersion characteristics; electrical frequency response; finite-element software; mechanical displacement measurement; solidly-mounted BAW resonator; Acoustic measurements; Acoustic waves; Finite element methods; Frequency measurement; Frequency response; Mechanical variables measurement; Predictive models; Resonance; Shape; Solid modeling;
Conference_Titel :
Ultrasonics Symposium, 2008. IUS 2008. IEEE
Conference_Location :
Beijing
Print_ISBN :
978-1-4244-2428-3
Electronic_ISBN :
978-1-4244-2480-1
DOI :
10.1109/ULTSYM.2008.0376
