School of Electronic Information and Electrical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
School of Electronic Information and Electrical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; Graduate School of Engineering, Chiba University, Chiba 263-8522, Japan.
Ultrasonics. 2018 Aug;88:131-136. doi: 10.1016/j.ultras.2018.03.017. Epub 2018 Mar 31.
This paper proposes a general finite element method (FEM)-based wavenumber domain analysis (WDA) to calculate scattering characteristics of surface acoustic wave (SAW) on arbitrary piezoelectric substrates. We add a damping loss mechanism (DLM) to the SAW injection port to avoid interferences from the incident and backscattered modes. After checking the validity of the proposed method, we calculate and study Sezawa mode scattering using a small number of electrodes on the ScAlN/3CSiC structure for demonstration. The frequency dependences of reflection and transmission coefficients and that of the power dissipation ratio for different termination conditions and electrode thicknesses are calculated. Also, the influence of base substrate materials and that of gratings on scattering parameters are explored. Investigation results demonstrate that high reflectivity with suppressed mode conversion can be obtained for the ScAlN-based layer structure if a base substrate with an extremely large velocity is used and if proper grating design is applied.
本文提出了一种基于广义有限元法（FEM）的波数域分析（WDA），用于计算任意压电衬底上表面声波（SAW）的散射特性。我们在 SAW 注入端口添加了一个阻尼损耗机制（DLM），以避免入射和反向散射模式的干扰。在验证了所提出方法的有效性后，我们使用 ScAlN/3CSiC 结构上的少量电极计算并研究了 Sezawa 模式散射。计算了不同终止条件和电极厚度下的反射和透射系数以及功率耗散比的频率依赖性。此外，还探讨了基底衬底材料和光栅对散射参数的影响。研究结果表明，如果使用具有极大速度的基底衬底并应用适当的光栅设计，则可以为基于 ScAlN 的层结构获得高反射率和抑制模式转换。
