Design and Simulation Studies on Linearised MEMS Capacitive Accelerometers with different Beam Springs

Abstract: Capacitive accelerometers based on change in air gap measurement often experiences non-linearity. In order to overcome this drawback, the overlapping area of the device is changed which produces linear output. In this paper, four different types of beam springs (viz. Half-folded spring, Meander spring, Serpentine spring and Zig-Zag spring) were introduced in the capacitive accelerometer structure. All the springs are subjected to different accelerations and linear outputs are obtained. The cross-axis performance of the four springs is compared. Among the four springs, Half- folded spring and Serpentine spring provide low cross-axis sensitivity. The structures are designed, analysed and simulated using IntelliSuite software.

Keywords: Capacitive accelerometer; Overlapping area; Beam Springs; Cross-axis sensitivity; Intellimask.