AI Article Synopsis
- The phase velocity of surface acoustic waves (SAW) changes when interacting with conductive materials above the wave propagation plane.
- A method is proposed to approximate the scattering matrix for specifically shaped conductive structures, focusing on a slotted beam used in a SAW-MEMS microaccelerometer.
- The study reveals that small adjustments in the beam's size can lead to significant variations in reflection and transmission coefficients, and the slotted beam behaves like a bandpass filter with a linear phase response.
Article Abstract
Phase velocity of a surface acoustic wave (SAW) varies when the electric field associated with the wave interacts with a conductive material located above the propagation plane. In this paper, we propose a general method to approximate the scattering matrix when the conductive structure has a specific geometry. This structure has reflective properties of SAW. As an example, we considered a previously reported SAW-MEMS microaccelerometer which mainly consists of a slotted beam. By applying this method, we obtained the relationship between acceleration and the reflection and transmission coefficients. The dynamic of the slotted beam was studied using the finite element method (FEM). It was observed that relatively small variations in the size of the microstructure could cause significant changes in the reflection and transmission coefficients. We also show that the slotted beam acts as an acoustic wave bandpass filter, and its response is similar to that of reflective gratings, but with linear phase.
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| http://dx.doi.org/10.1109/TUFFC.2011.1965 | DOI Listing |
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