Mechanical design and characterization of a resonant magnetic field microsensor with linear response and high resolution

Torsional MEMS magnetometer operated off-resonance for in-plane magnetic field detection

“…Magnetometers can be used to determine the absolute orientation, so 5 for heading purposes, and to improve navigation capabilities when coupled to gyroscopes and accelerometers. Though some works propose the integration of magnetic thin layers on top of suspended MEMS structures [2], most of the literature about MEMS magnetometers rely on the Lorentz force principle, as this concept allows avoiding magnetic materials and the corresponding need 10 for relatively low temperature during the fabrication steps (some magnetic materials begin losing their properties above about 300 ). Early works [3] and several thereafter [4,5,6] mostly focused on Lorentz-force devices to measure out-of-plane magnetic fields.…”

“…Early works [3] and several thereafter [4,5,6] mostly focused on Lorentz-force devices to measure out-of-plane magnetic fields. Few examples of in-plane (either differential or non-differential) MEMS magnetometers were also described in the literature 15 [7,8,9,10,11,12,13]. The performances of all these devices, from a system point of view, are limited by a critical trade-off between resolution and bandwidth when operated at resonance: the former improves, the latter worsens with decreasing damping coefficients (obtainable e.g.…”

A MEMS-based magnetic field sensor with simple resonant structure and linear electrical response

“…c o m / l o c a t e / m e e an external magnetic field. After, Herrera-May et al [17] designed a magnetic field sensor formed by a seesaw rectangular loop (700 × 400 × 5 μm) of thin silicon beams, a single aluminum coil, and a piezoresistive sensing technique. It presented a resonant frequency of 22.99 kHz, a quality factor of 96.6 at atmospheric pressure, a power consumption close to 16 mW, and a sensitivity of 1.94 V·T −1 .…”

Mechanical characterization and modelling of Lorentz force based MEMS magnetic field sensors

“…To this end dynamic resonant tests are combined with topography scans and thermomechanical finite element simulations. The sensitivity of the sensors in air was also obtained using a setup which is described in detail in [33].…”