Resonant Accelerometer with Compliant Parallel Motion Linkage Force Amplification Mechanism

Abstract

We report on a novel architecture of a resonant accelerometer incorporating four proof masses and a compliant parallel motion linkage as a force amplifier. A simple, Manhattan geometry, manufacturable, device is distinguished by low parasitic compliance and purely axial, lacking any bending, loading of the sensing beams. Silicon on insulator (SOI) devices were operated in open loop and in a non-differential mode, the acceleration was emulated by an electrostatic force. Consistently with the model prediction a sensitivity of ≈ 2.3 Hz/V2, which is equivalent to ≈ 417 Hz/g, was experimentally demonstrated in a Si device with ≈ 500 µm × 480 µm × 25 µm masses and 250 µm long and ≈ 1.5 µm wide resonant sensing beams.