Low-g Area-changed MEMS Accelerometer Using Bulk Silicon Technique
Badariah Bais and Burhanuddin Yeop Majlis
DOI : 10.3844/ajassp.2008.626.632
American Journal of Applied Sciences
Volume 5, Issue 6
A bulk micromachined accelerometer based on an area variation capacitive sensing for low-g applications was developed. The accelerometer was designed with ribbed-style fingers structure on the movable mass connected in parallel and suspended over stationary electrodes composed of differential comb fingers by means of suspension beams anchored onto the substrate. A folded, rigid truss suspension design with low spring constant and low cross-axis sensitivity was chosen. The simulation was performed using Coventorware software. A three-mask bulk micromachining wafer bonding fabrication process was utilized to realize the accelerometer. Silicon-on-glass was used to achieve high sensitivity and low mechanical noise while maintaining a simple structure. The general concept, main design considerations, fabrication procedure and performance of the resulted accelerometer was elaborated and presented. A linear relationship between the differential capacitance and acceleration was obtained. The accelerometer sensitivity was calculated to be 0.47 pF/g with an acceleration range of Â±5 g.
© 2008 Badariah Bais and Burhanuddin Yeop Majlis. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.