一种MEMS陀螺仪的飞秒激光修调方法

受微加工工艺条件限制,MEMS敏感结构的尺寸等关键参数的相对误差较大,使其在宏观上表现出非理想的运动特性,性能指标也难以满足高精度应用的要求。为消除加工误差的影响,分析了一种MEMS陀螺仪的运动特性和误差耦合机理,提出了一种通过飞秒激光对敏感结构的梁进行刻蚀修调的方法。MEMS陀螺修调前后的运动特性试验表明,修调后的误差系数比修调前降低了50%以上,而误差的稳定性则比修调前提高了约70%,证明提出的飞秒激光刻蚀方法能够抑制微加工误差的影响,提高MEMS陀螺仪的性能。

Trimming method for MEMS gyroscope by femtosecond laser

The micro-fabricated MEMS gyroscopes usually do not meet the high-precision application requirements due to the precision limits in micro-fabrication processes.In order to eliminate the fabrication defects,the motion modes and the error coupling mechanisms of the sensing element of a MEMS gyroscope are studied and analyzed,and a trimming method by femto-second laser etching on folded-beam structures is proposed to realize the high-quality etching process.The fabrication system is built based on the femtosecond laser,which integrates a series of units and their control system.Dynamic test results show that,after etched by laser pulses,the coupling error coefficient is reduced by more than 50％,and the error's stability is improved by nearly 70％,which prove the feasibility and effectiveness of the proposed trimming method in suppressing the fabrication errors and improving the gyroscope's performance.