Design and analysis of CMOS MEMS based single proof mass Tri-axial capacitive accelerometer with readout integrated circuit

• Published in: 2017 First International Conference on Latest trends in Electrical Engineering and Computing Technologies (INTELLECT) pp. 1 - 8
• Main Authors: Shahbaz, Muhammad Aaquib, Warsi, Zain Hussain, Irshad, Shahzadi Mahaa, Irshad, Shahzada Tahaa, Jawed, Syed Arsalan
• Format: Conference Proceeding
• Language: English
• Published: IEEE 01.11.2017
• Subjects: Acceleration; Accelerometers; Capacitance; CMOS-MEMS; Coventor's MEMS; Differential position-sense interface; Integrated circuits; Micromechanical devices; ROIC; Sensitivity; Sensors; Tri-axis Accelerometer
• DOI: 10.1109/INTELLECT.2017.8277644

In this paper, a Monolithic CMOS-MEMS (MicroElectroMechanical Systems) based Tri-axis Accelerometer with complete Readout Integrated Circuit (ROIC) implemented using 150nm one-poly-Silicon and six-metal/dielectric CMOS-MEMS process. The multilayer stacking features of the CMOS-MEMS process were exploited to integrate the in-plane (x and y axes) and out-of-plane (z-axis) capacitive sensing electrodes. Thus, the three-axis sensing electrodes can be integrated on a single proof mass to reduce the overall footprint of the Accelerometer. Moreover, the fully differential sensing electrodes among all three axes are implemented to increase the sensitivities and decrease the noise. The accelerometer structure was designed and simulated using Coventor's MEMS+. The Accelerometer measures changes in capacitance between the electrodes to detect detections of a proof mass, which result from external acceleration input. The capacitive MEMS structure is connected to a differential position-sense interface that gives the output Voltage in accordance with change in capacitance.