Research on temperature characteristic of parasitic capacitance in MEMS capacitive accelerometer

• Published in: Sensors and actuators. A. Physical. Vol. 285; pp. 581 - 587
• Main Authors: Dong, Xianshan, Huang, Qinwen, Xu, Wei, Tang, Bin, Yang, Shaohua, Zhu, Junhua, En, Yunfei
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.01.2019; Elsevier BV
• Subjects: Accelerometers; Bias; Bias drift; Capacitance; Closed loop systems; Drift; Electrodes; MEMS accelerometer; Microelectromechanical systems; Parasitic capacitance; Temperature; Temperature characteristic; Bias drift; MEMS accelerometer; Temperature characteristic; Parasitic capacitance
• ISSN: 0924-4247; 1873-3069
• DOI: 10.1016/j.sna.2018.12.001

•Temperature characteristics of parasitic capacitance of typical MEMS capacitive accelerometers are quantificationally revealed.•Contribution of the parasitic capacitance on bias temperature drift is separated from other factors for the first time.•New direction of improving the temperature performance of MEMS capacitive accelerometer is clarified. In MEMS capacitive accelerometer, parasitic capacitance is a serious problem, and its change over temperature would deteriorate performance of MEMS accelerometer. Yet, the temperature characteristic of parasitic capacitance hasn’t got enough research. In this work, the parasitic capacitance and its effect on bias drift are quantificationally studied over temperature. The results of MEMS comb-finger and sandwich accelerometers show that parasitic capacitance affects bias temperature drift seriously and it can even become main factor. Moreover, contribution of the parasitic capacitance on bias drift is separated from other factors for the first time, and new methods of decreasing the drift of bias and nonlinearity are proposed. This work provides a new way for the research on bias drift of closed-loop MEMS capacitive accelerometer and is helpful for improving temperature performance of capacitive accelerometer.