Novel mode-coupling vibrations of AlN thin film bulk acoustic resonator operating with thickness-extensional mode  

作　　者：Zinan ZHAO Nian LI Yilin QU Weiqiu CHEN 

机构地区：[1]Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province and Department of Engineering Mechanics,Zhejiang University,Hangzhou 310027,China [2]Huanjiang Laboratory,Zhuji 311816,Zhejiang Province,China [3]Suzhou HunterSun Electronics Co.,Ltd.,Suzhou 215124,Jiangsu Province,China [4]School of Marine Science and Technology,Northwestern Polytechnical University,Xi’an 710072,China

出　　处：《Applied Mathematics and Mechanics(English Edition)》2023年第12期2187-2206,共20页应用数学和力学（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Nos.11872329,12192211,and 12072315);the Natural Science Foundation of Zhejiang Province of China(No.LD21A020001);the National Postdoctoral Program for Innovation Talents of China(No.BX2021261);the China Postdoctoral Science Foundation Funded Project(No.2022M722745)。

摘　　要：The dispersion curves of bulk waves propagating in both AlN and ZnO film bulk acoustic resonators(FBARs)are presented to illustrate the mode flip of the thickness-extensional(TE)and 2nd thickness-shear(TSh2)modes.The frequency spectrum quantitative prediction(FSQP)method is used to solve the frequency spectra for predicting the coupling strength among the eigen-modes in AlN and ZnO FBARs.The results elaborate that the flip of the TE and TSh2 branches results in novel self-coupling vibration between the small-wavenumber TE and large-wavenumber TE modes,which has never been observed in the ZnO FBAR.Besides,the mode flip leads to the change in the relative positions of the frequency spectral curves about the TE cut-off frequency.The obtained frequency spectra can be used to predict the mode-coupling behaviors of the vibration modes in the AlN FBAR.The conclusions drawn from the results can help to distinguish the desirable operation modes of the AlN FBAR with very weak coupling strength from all vibration modes.

关 键 词：AlN film mode flip frequency spectrum quantitative prediction(FSQP) dispersion curve mode-coupling vibration 

分 类 号：TN751.2[电子电信—电路与系统]