CAJ | 학술논문

研究MEMS电容式加速度传感器的自我标定方法,模拟机械振动台标定,提高标定效率和降低标定成本,并从理论上分析了DRIE工艺误差对传感器自我标定精度的影响。分析的传感器模型梳齿间距为4μm,厚度80μm,传感器自我标定以模拟幅值为1 g的振动台标定为例,针对DRIE工艺加工的高深宽比梳齿电容存在正负侧壁倾斜角α的情况,分析了该倾斜角对梳齿式传感器自我标定的影响。分析结果表明：传感器工作在开环电路时,梳齿的倾斜对传感器自我标定影响明显,且随着倾斜角度的增大而增大。与梳齿完全平行时传感器的自我标定相比,倾斜角为±0.1°时,自我标定误差约为10%；倾斜角为0.5°时,自我标定误差约为27%；倾斜角为-0.5°时,极板发生吸合。表明传感器工作在开环电路时,梳齿的倾斜角对传感器的自我标定影响明显,而传感器工作在闭环电路时,梳齿的倾斜对自我标定的影响明显降低,当倾斜角小于±0.5°时,自我标定的误差小于0.6%,理论误差接近于激光干涉仪绝对标定法的误差(0.5%~1%),证明了自我标定方法的可行性。还分析了倾斜角影响自我标定精度的原因以及提出了开环自我标定时减小倾斜角误差的方法,并阐述了具体的修正步骤。
연구MEMS전용식가속도전감기적자아표정방법,모의궤계진동태표정,제고표정효솔화강저표정성본,병종이론상분석료DRIE공예오차대전감기자아표정정도적영향。분석적전감기모형소치간거위4μm,후도80μm,전감기자아표정이모의폭치위1 g적진동태표정위례,침대DRIE공예가공적고심관비소치전용존재정부측벽경사각α적정황,분석료해경사각대소치식전감기자아표정적영향。분석결과표명：전감기공작재개배전로시,소치적경사대전감기자아표정영향명현,차수착경사각도적증대이증대。여소치완전평행시전감기적자아표정상비,경사각위±0.1°시,자아표정오차약위10%；경사각위0.5°시,자아표정오차약위27%；경사각위-0.5°시,겁판발생흡합。표명전감기공작재개배전로시,소치적경사각대전감기적자아표정영향명현,이전감기공작재폐배전로시,소치적경사대자아표정적영향명현강저,당경사각소우±0.5°시,자아표정적오차소우0.6%,이론오차접근우격광간섭의절대표정법적오차(0.5%~1%),증명료자아표정방법적가행성。환분석료경사각영향자아표정정도적원인이급제출료개배자아표정시감소경사각오차적방법,병천술료구체적수정보취。
This paper studies the self-calibration of MEMS capacitive accelerometer to simulate the vibrator to increase the efficiency and reduce the cost of calibration,and analyses the effect of DRIE fabrication error on self-calibration of sensors theoretically. The gap of the sensor used in this paper is 4 μm,and the thickness is 80 μm. The self-calibration of sensors simulates the calibration of mechanical vibrator which is vibrating at an amplitude of 1 gn. As the combs of the capacitive sensors fabricated by deep reactive ion etching(DRIE)exist plus-minus slope angle α,this paper analyses the effect of the slope angle on the self-calibration of MEMS capacitive accelerometer. The results show that the error caused by slope angle is obvious,which gets more obvious with bigger slope angle in open loop circuit. Comparing with the self-calibration of parallel comb sensors,the error of self-calibration is about 10% when the slope angle is ±0. 1°;27% when the slope angle is 0. 5°;and pull-in occurs when the slope angle is-0. 5°. It proves that in open-loop circuit,the slope angle affacts the self-calibration obviously. But the error gets much lower when sensor is in close loop circuit. When the slope angle is less then±0. 5°,the error of self-calibration is less than 0. 6%,which is close to the error of the absolute calibration of Laser Interferometer(0. 5% ~1%),and proves that the method of self-calibration is practicable. Meanwhile,this paper analyses the reasons how slope angle affact self-calibration,and come up with an idea which can lower the error of self-calibration that caused of slope angle in open loop circuit and state the specific measure.