带有阶梯沟槽结构音叉型石英晶体谐振器设计研究

Design and study of tuning fork type crystal resonator with stepped groove structure

为了解决表面贴装器件(SMD)型压电石英音叉晶体的振动阻抗过大的问题,提出了一种带有阶梯沟槽结构的Z切压电石英音叉晶体谐振器。首先,从振动原理上结合压电石英晶体各向异性材料因腐蚀工艺导致结构的不对称性解释阻抗过大的机理;然后,提出一种新结构弥补因腐蚀工艺带来音叉晶体结构不对称的问题。基于有限元仿真计算出音叉晶体谐振器的振动分布情况,通过仿真分析发现新型结构有效降低音叉双叉振梁面内弯曲的不对称性,改善了音叉晶体谐振器的振动特性,降低了器件的阻抗。

In order to solve the problem of excessive vibration impedance of surface mounted device(SMD)type piezoelectric quartz tuning fork crystal,a Z-cut piezoelectric quartz tuning fork crystal resonator with stepped groove structure is proposed.Firstly,the mechanism of excessive impedance by combining the vibration principle with the structural asymmetry caused by the corrosion process of piezoelectric quartz crystal anisotropic materials is explained.Then,a new structure is proposed to make up for the defects of asymmetric structure caused by the corrosion process.Based on the finite element simulation calculation,the vibration distribution of the tuning fork crystal resonator is given.It is found through simulation analysis that the new structure effectively reduces the asymmetry of in-plane bending of the double-fork vibration beam of the tuning fork,the vibration characteristics of the tuning fork crystal resonator are improved,and the impedance of the device is reduced.