一种薄膜体声波谐振器的设计与验证

为简化薄膜体声波谐振器薄膜厚度的设计,提出一种薄膜体声波谐振器薄膜厚度的设计方法。仿真结构由诱导层和其上层的电极层-压电层-电极层的三明治结构组成。在最优有效机电耦合系数下确定初始薄膜体声波谐振器的薄膜厚度;然后确定诱导层厚度及其相应的频偏值;使用频偏值补偿并联谐振频率,重新计算补偿后的薄膜体声波谐振器中电极层与压电层的最优厚度比值,并使用COMSOL Multiphysics进行仿真验证。当并联谐振频率为3.60 GHz时,100 nm的氮化铝的频偏值为0.20 GHz。氮化铝的有效机电耦合系数最优为5.907%,进行频率补偿后,氮化铝的串联谐振频率和并联谐振频率分别为3.48 GHz和3.60 GHz,设计方法得到了验证。诱导层有效地优化了压电层C轴特性,减少了能量损耗。

Design and verification of a film bulk acoustic resonator

In order to simplify the design of the film thickness of the film bulk acoustic resonator, a design method for film bulk acoustic resonator film thickness is proposed. The simulation structure consists of the induced layer and the upper electrode-piezoelectric-electrode sandwich structure. The initial film of the film bulk acoustic resonator is designed by the optimal effective electromechanical coupling coefficient, and then the thickness of the induced layer and the corresponding frequency offset value are determined. The parallel resonant frequency is compensated with the frequency offset, and then the film thickness of the electrode and the piezoelectric are recalculated. Finally, the structure is simulated by COMSOL. When the parallel resonant frequency is 3.60 GHz, the frequency offset value of the 100 nm AlN is 0.20 GHz. The effective electromechanical coupling coefficient of the AlN is 5.907%. After frequency compensation, the series resonant frequency and parallel resonant frequency of the AlN are 3.48 GHz and 3.60 GHz, respectively. The design method is verified. The induced layer effectively optimizes the C-axis characteristics of the piezoelectric layer and reduces energy loss.