基于表面声波效应的惯性器件研究

发布时间：2018-03-26 06:44

本文选题：表面声波　切入点：陀螺　出处：《西安工业大学》2017年硕士论文

【摘要】：陀螺仪是广泛应用在汽车导航和武器制导领域的重要部分,而基于表面声波陀螺的惯性器件相对于传统的MEMS振动陀螺具有抗冲击能力强、高可靠性和低成本等优势。本文基于惯性力作用下的材料中表面声波特性的变化规律,利用COMSOL软件对表面声波陀螺的谐振器结构进行了仿真,利用光刻技术对表面声波陀螺进行了制备和性能检测与分析。得到以下结论:(1)表面声波特性的研究,首先通过理论分析与MATLAB仿真,得到表面声波的波速随旋转角速度的增大而减小。其次,结合COM理论模型,对叉指换能器结构进行分析,利用COM参数和P矩阵推导出导纳特性。(2)根据波速与旋转角速度的变化关系,利用有限元分析软件对基于128°YX-LiNbO3的表面声波谐振器结构进行了多物理域耦合建模与仿真,提取了对称模态和反对称模态的变形图,计算出128°YX-LiNbO3的表面声波相速度是3917m/s和机电耦合系数是4.71%。针对128°YX-LiNbO3的表面声波谐振器的频率特性,分析得到,器件结构中随着叉指换能器的敷金比的逐渐增大,对称模态与反对称模态的特征频率逐渐减小;压电基底的厚度在大于一个波长时对特征频率影响较小;而金属电极厚度每增加10nm和厚度的均匀性每变化1nm,对称模态的特征频率基本保持不变,反对称模态的特征频率变化0.002MHz。(3)通过频率响应分析,获得电导、导纳与频率之间的关系图。加入旋转角速度,得到频率随旋转角速度的变化关系呈线性关系。(4)利用光刻技术和磁控溅射制备测得金属膜层的平均厚度在为150nm,金属电极宽度为12.555μm,频率响应为81.6MHz。由此制作的新型表面声波陀螺沿X轴方向的灵敏度为 100.44 Hz/deg/s。
[Abstract]:Gyroscope is an important part of vehicle navigation and weapon guidance, and the inertial device based on surface-acoustic gyroscope has stronger impact resistance than traditional MEMS vibratory gyroscope. Based on the variation of surface acoustic wave characteristics in materials under inertial force, the resonator structure of surface acoustic gyroscope is simulated by using COMSOL software, which has the advantages of high reliability and low cost. The surface acoustic gyroscope has been fabricated and tested and analyzed by photolithography. The following conclusions are obtained: 1) the study of surface acoustic wave characteristics. Firstly, the theoretical analysis and MATLAB simulation are used to study the acoustic properties of the surface acoustic gyroscope. The wave velocity of the surface acoustic wave decreases with the increase of the rotational angular velocity. Secondly, the structure of the cross finger transducer is analyzed with the COM theory model. According to the relationship between wave velocity and rotational angular velocity, the coupling modeling and simulation of surface acoustic resonator structure based on 128 掳YX-LiNbO3 is carried out by using finite element analysis software. The deformation diagrams of symmetric mode and antisymmetric mode are extracted, and the phase velocity of surface acoustic wave of 128 掳YX-LiNbO3 is calculated to be 3917m/s and the electromechanical coupling coefficient is 4.71. According to the frequency characteristics of surface acoustic wave resonator with 128 掳YX-LiNbO3, the results are obtained. The characteristic frequencies of symmetric mode and antisymmetric mode gradually decrease with the increase of the ratio of interDigital transducer to gold, and the thickness of piezoelectric substrate has little effect on the characteristic frequency when the thickness of piezoelectric substrate is greater than one wavelength. However, when the thickness of the metal electrode increases 10nm and the uniformity of the thickness changes 1 nm, the characteristic frequency of the symmetric mode remains basically unchanged, and the characteristic frequency of the antisymmetric mode changes 0.002 MHz. 3) the conductance is obtained by frequency response analysis. Diagram of the relationship between admittance and frequency. The linear relationship between frequency and rotational angular velocity is obtained. (4) the average thickness of metal film is 150 nm, the width of metal electrode is 12.555 渭 m, and the frequency response is 81.6 MHz by photolithography and magnetron sputtering. The sensitivity of the surface-acoustic gyroscope along the X axis is 100.44 Hz / degr / s.
【学位授予单位】：西安工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN65

【参考文献】