电极对薄膜体声波谐振器性能的影响  

Influence of Electrode on the Electrical Characteristics of Film Bulk Acoustic Resonator

作　　者：焦向全[1] 张睿[1] 马晋毅[2] 杜波[2] 钟慧[1] 石玉[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 [2]中国电子科技集团公司第二十六研究所,重庆400060

出　　处：《压电与声光》2015年第3期373-376,共4页Piezoelectrics & Acoustooptics

基　　金：国家自然基金资助项目(61101038);四川关键技术研究发展基金资助项目(2011GZ0220)

摘　　要：采用有限元分析软件COMSOL Multiphysics仿真了三维结构的谐振器,探讨了不同的顶电极形状对谐振器性能的影响。有效机电耦合系数(k2teff)随电极-压电层厚度比增大而减小,其中电极形状为三角形的谐振器在厚度比为0.05时获得最大k2teff(5.73%)。品质因数Q值变化趋势与k2teff相反,由三角形电极在厚度比为0.25时,获得最大Q值为1 314。不同电极形状的谐振器的优值随电极-压电厚度比先增大后减小,最大值为65.4,由正方形电极在比值为0.15时获得。A finite element method analyzing software of COMSOL Multiphysics was used to simulate the 3D bulk acoustic wave （BAW） resonator. The influences of different types of top electrodes to the characteristics of BAW were discussed. The effective electromechanical coupling coefficient was decreased with the increase of thick- ness ratio of electrode to piezoelectric layer. The maximum k2teff of 5.73% was achieved at the thickness ratio of 0.05 with the triangular top electrode. The Q-value had a trend opposite to k2teff. The maximum value was 1 314, which was also obtained with the triangular electrode at the thickness ratio of 0.25. The figure of merit first increased and then reduced with the increase of thickness ratio of electrode to piezoelectric layer. The maximum value was 65.4 achieved at the thickness ratio of 0.15 with the square electrode.

关 键 词：薄膜体声波谐振器 有限元 有效机电耦合系数 品质因数 COMSOL 

分 类 号：TN713.2[电子电信—电路与系统]