面向陀螺应用的硅基大尺寸楔角型谐振腔

Large dimension wedge-resonator on silicon chip for gyro application

针对集成光学陀螺中核心敏感单元难以同时实现集成化和高灵敏度问题,提出了硅基二氧化硅楔角型谐振腔的制作方案。通过理论分析得出,由光电探测器散弹噪声引起的陀螺极限灵敏度与谐振腔的直径和品质因数乘积(D×Q)成正比。运用MEMS工艺,制作出直径达1.5 cm、楔角22°的谐振腔;通过控制氧化硅腐蚀时掩膜层的参数,获得了不同楔角的谐振腔,并论述了腐蚀楔角跟掩膜层参数的关系。通过耦合测试,该谐振腔品质因数为2×106,理论上采用上述谐振腔研制的陀螺,其极限灵敏度可达6(°)/h。

For the problem that core sensitive unit of integrated optic gyro is difficult to realize integration and high sensitivity, a program of fabricating silica wedge-resonator was proposed. Through the theoretical analysis, the ultimate resolution of the gyro caused by the photo-detector shot noise was proportional to the product of the diameter and the quality factor of the resonant cavity. Wedge cavity of1.5 cm diameter and 22° wedge angle was produced by MEMS（micro-electromechanical systems） process;resonant cavities with different wedge angles were acquired by controlling the mask layer parameters; the relationship between mask layer parameters and wedge angles quality was discussed. Through the coupling test, the quality factor of the resonator is 2 ×106, the theoretical sensitivity of 6（°）/h is achieved for the gyroscope based on the resonator fabricated.