A high performance acceleration sensor concept is presented, which combines multiple wafer bonding and differential capacitance measurement into a point-symmetrical design. The accelerometer is a four-layer glass/Si/Si/glass structure realized with a combination of Si/Si fusion bonding and Si/glass anodic bonding. Fusion bonding with wafer-to-wafer alignment is performed on preprocessed silicon. Glass covers are bonded onto both wafer sides in a single anodic bonding sequence with polarity reversal. The main device characteristics are an exclusive response to a translational acceleration component in a single axis and maximized sensitivity for a given chip area. Modifiable damping characteristics and hence adjustable bandwidth is an additional device feature. This is obtained by controlling the gas pressure and composition during anodic bonding of the glass covers.
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