基于SiO2掩膜层的硅基微半球谐振子模具加工工艺

微半球模具的三维对称性对半球谐振子的性能有着决定性的影响。提出使用热氧化工艺生长的SiO2材料作为掩膜层,以达到在使用HNA腐蚀溶液制作微半球陀螺谐振子模具的过程中加快纵向腐蚀速率及实现半球模具三维对称的目的。详细研究了不同腐蚀窗初始半径下HNA腐蚀溶液对〈111〉单晶硅进行纵向和侧向腐蚀时,其腐蚀深度和腐蚀速率的演化规律,并在此基础上通过设置适当的腐蚀窗初始半径(5μm)以及腐蚀时间(15 min),成功制作出了半径为38.937 7μm的三维对称半球谐振子模具,通过球度拟合证明该模具整体半径方差为0.789 3μm,球度偏差为2%,为半球谐振子三维对称性的提升奠定了基础。

Fabrication Technology of Si-Based Micro-Hemispherical Resonator Molds Based on SiO2 Mask Layer

The three dimensional symmetry of the micro-hemispherical mold has the decisive influence on the performance of the hemispherical resonator.In the process of manufacturing the micro-hemispherical resonator mold by using HNA etching solution,with SiO2 grown by thermal oxidation process as a mask layer,the longitudinal etching rate was accelerated and the three-dimensional symmetry of hemispheric mold was achieved.The evolution of longitudinal/lateral etching depths and etching rates of〈111〉single crystal silicon etched by HNA etching solution under different etching window initial radius were studied in detail.And based on that,the threedimensional symmetrical hemispherical resonator mold with a radius of 38.937 7μm was successfully processed by setting the appropriate etching window initial radius(5μm)and etching time(15 min).With the sphericity fitting,it is proved that the overall radius variance of the mold is 0.789 3μm and the sphericity deviation is 2%,laying a foundation for improvement the threedimensional symmetry of hemispherical resonators.