AlN/PZT复合压电薄膜层SAW激励与传播研究  

Research on Excitation and Propagation of Surface Acoustic Wave in AlN/PZT Composite Piezoelectric Film

作　　者：文芷菁 张涛[1] 柯贤桐 刘鑫鑫 曹晓闯 ALIREZA Baghai Wadji WEN Zhijing;ZHANG Tao;KE Xiantong;LIU Xinxin;CAO Xiaochuang;ALIREZA Baghai Wadji(College of Science,Xi’an University of Science and Technology,Xi’an 710054,China)

机构地区：[1]西安科技大学理学院,陕西西安710054

出　　处：《压电与声光》2022年第2期205-209,共5页Piezoelectrics & Acoustooptics

基　　金：国家自然科学基金资助项目(No.52174151,No.11974275,No.61834005);陕西省联合基金重点资助项目(2021JML-05);陕西省重点科技创新团队基金资助项目(2019TD-026);陕西省科技统筹创新工程计划基金资助项目(2012KTCL01-12);陕西省榆林市科技局基金资助项目(2019-138)。

摘　　要：该文在单晶硅基底上设计了AlN/PZT复合压电薄膜层声表面波(SAW)器件,采用有限元法(FEM)研究了复合压电材料厚度(PZT厚度h_(PZT)和AlN厚度h_(AlN))对AlN/IDT/PZT/Si结构中零阶、一阶SAW的相速度、机电耦合系数和电极反射系数的影响,根据色散特性得到最优化薄膜厚度。结果表明,AlN/IDT/PZT/Si结构中,当h_(PZT)=0.025λ,h_(AlN)=λ时,零阶、一阶SAW都能取得最高相速度(分别为5582 m/s和5711 m/s),适用于高频器件设计;在h_(PZT)=0.2λ,h_(AlN)=0.1λ时,零阶SAW波的机电耦合系数最大(为21.55%),但此时相速度最小(仅为2890 m/s),适用于移动通信领域宽带低损耗SAW滤波器和延迟线结构信号处理器件的设计。In this paper,the AlN/PZT composite piezoelectric thin film layer SAW device on the monocrystalline silicon substrate was designed.The finite element method was used to study the influences of the thickness of composite piezoelectric material(the PZT thickness hPZT and AlN thickness hAlN)on the phase velocity of zero-order SAW and first-order SAW,electromechanical coupling coefficient and electrode reflection coefficient in AlN/IDT/PZT/Si structure.According to the dispersion characteristics,the optimum film thickness was obtained.The results show that when h_(PZT)=0.025λand h_(AlN)=λin AlN/IDT/PZT/Si structure,the highest phase velocities of the zero-order and first-order SAW are 5582 m/s and 5711 m/s respectively,which are suitable for the design of high frequency devices.When h_(PZT)=0.2λ,h_(AlN)=0.1λ,the electromechanical coupling coefficient of zero-order SAW wave is the highest of 21.55%,but the phase velocity is the smallest of only 2890 m/s,which is suitable for the design of the signal processing devices of wideband low loss surface acoustic wave filter and delay linear structure in the mobile communication field.

关 键 词：声表面波(SAW) 复合压电薄膜 声激励 声传播 色散 

分 类 号：TN61[电子电信—电路与系统] TN384