高阶兰姆波MEMS声表面波谐振器仿真研究  

Simulation Study of High-order Lamb Wave MEMS SAW Resonator

作　　者：陈鹏[1] 张万里[1] 彭斌[1] 李川[1] 舒琳[1] 王瑜[1] 

机构地区：[1]电子科技大学电子薄膜与集成器件国家重点实验室,四川成都610054

出　　处：《压电与声光》2014年第6期876-879,共4页Piezoelectrics & Acoustooptics

基　　金：国家自然科学基金资助项目(61223002)

摘　　要：以有限元法为基础,对高阶兰姆波型微机电系统(MEMS)声表面波谐振器进行了仿真。研究了压电材料及其厚度、Si基底厚度对高阶兰姆波声速的影响规律,结果表明,AlN压电薄膜器件的高阶兰姆波的声速比ZnO和LiNbO3器件更大。压电材料较薄时传播兰姆波,太厚时则传播瑞利波。高阶兰姆波的声速随着硅基底厚度增加而逐渐降低,并趋于一个稳定值。在此基础上,提出了在电极上方加载一层压电薄膜来提高兰姆波声速的器件结构,仿真结果表明,通过增加一层AlN薄膜,可提高高阶兰姆波的声速,进而提高器件的谐振频率。Based on the finite element method, the high order Lamb wave MEMS SAW resonator was simula ted. The effects of piezoelectric material, the thickness of piezoelectric material and the thickness of Si substrate on the velocity of high-order Lamb wave were researched. The results showed that the velocity of high-order Lamb wave of the AIN film resonator was higher than that of the ZnO or LiNbO3 resonators. Lamb waves were excited when the piezoelectric film was thin enough, hut Rayleigh waves were excited when the piezoelectric film was thick enough. The velocity of high-order Lamb wave tended to be stable with the increase of the thickness of Si substrate. A structure of devices with a layer of piezoelectric film on the IDT were designed and simulated. The simulation results showed that the velocity of high order Lamb was increased by adding a layer of A1N film on IDT, thereby, the resonant frequency of devices were increased.

关 键 词：有限元法 声速 声表面波谐振器 高阶兰姆波 压电薄膜 

分 类 号：TN65[电子电信—电路与系统]