Fig. 5: In-plane MEMS magnetic field sensors driven by electrostatic force.

a Torsional plate resonator-based sensor actuated by parallel-plate electrodes⁹². SEM images show the fabricated structure with damping holes and an integrated induction coil. b Torsional frame resonator-based sensor using vertically interlaced comb drives that enlarge the actuation area and reduce air damping, thereby improving sensitivity and Q-factor. Measured output responses confirm low cross-axis interference and good linearity⁹³. c Two-axis MEMS magnetometer employing an eccentric resonator with a two-layer inductor⁹⁵. By switching the driving frequency, torsional resonance is excited along either the X- or Y-axis and enables vector detection of in-plane magnetic fields