Analog Devices, Inc.
Folded tether structure for MEMS sensor devices

Abstract:

A microelectromechanical systems (MEMS) sensor device with a compound folded tether is disclosed. The compound folded tether connects a movable proof mass to a substrate, and includes folds composed of multiple short segments aligned with each other to form a longer composite segment having multiple breaks along its length. The use of multiple short segments to create a longer composite segment of the folded tether provides the tether with increased stiffness without altering the fundamental resonance frequency of the tether. The increased stiffness can beneficially lower the occurrence of stiction. Moreover, such a tether configuration provides larger separation between the tether's fundamental resonance frequency and higher order resonant mode frequencies, meaning that the higher order modes may be suppressed in typical operation of the MEMS sensor device.