Highly coupled leaky surface acoustic wave on hetero acoustic layer structures based on ScAlN thin films with a c-axis tilt angle
Highly coupled leaky surface acoustic wave on hetero acoustic layer structures based on ScAlN thin films with a c-axis tilt angle
复制标题
c轴倾斜角ScAlN薄膜异质声层结构上的高耦合漏表面声波
DOI：
10.35848/1347-4065/abdc35
复制
发表时间：
2021-03-01
影响因子：
1.5
通讯作者：
Wang, Weibiao
中科院分区：
文献类型：
--
作者：
Liu, Huiling;Zhang, Qiaozhen;Wang, Weibiao
本文提出了一种具有c轴倾斜角度的基于ScAlN薄膜的异质声层结构。采用有限元法分析了不同欧拉角（0°，，psi）下ScAlN薄膜表面声波的激发模式及其传播特性。我们发现HAL结构的声场分布可以通过旋转它们的欧拉角来调节，并且正常的saw被抑制；而漏态saw （LSAWs）的机电耦合系数（K-2）显著提高。剪切水平（SH）型lsaw的最大K-2为14%，几乎是之前报道的正常SAW Sezawa模式的7倍。此外，由（0度、90度、60度）ScAlN薄膜/SiO2/AlN/Si组成的优化HAL结构同时具有更大的K-2、更宽的带宽和更高的Q值，为高性能宽带SAW器件的设计和应用提供了良好的前景。
In this paper, we present hetero acoustic layer (HAL) structures based on ScAlN thin films with a c-axis tilt angle. The surface acoustic wave (SAW) excitation modes and their propagation characteristics for different Euler angles (0 degrees, , psi) of the ScAlN thin film are analyzed using the finite element method. We find that the acoustic field distribution of HAL structures can be adjusted by rotating their Euler angles and that normal SAWs are suppressed; however, leaky SAWs (LSAWs) with significantly improved electromechanical coupling coefficients (K-2) are excited. A maximum K-2 of 14% can be obtained for shear horizontal (SH)-type LSAWs, which is almost 7 times larger than that of the previously reported normal SAW Sezawa mode. Moreover, the optimized HAL structure consisting of (0 degrees, 90 degrees, 60 degrees) ScAlN thin film/SiO2/AlN/Si simultaneously possesses a larger K-2, a wider bandwidth, and a higher Q value, which is promising for the design and application of wideband SAW devices with high performance.