Fig. 10: MEMS electric-field sensors using out-of-plane torsional resonance of grounded shield.

a Structure of the electric field sensor with out-of-plane torsional driving via an electrostatic force between the driving electrode at the bottom and the grounded shield¹³⁶. b SEM images of the MEMS electric field sensor with a torsion-driven shield. c Movement of the grounded shield results in vertical displacement between the shield and the sensing electrode. At this time, the distribution of the electric field reaching the sensing electrode changes. This generates an induced current on the basis of changes in the charge. d Response plot of the MEMS electric field sensor. e A schematic illustration of the MEMS electric field sensor with torsional comb driving¹³⁸. f A SEM image of the sensor showing lateral integration of sensing and driving electrodes. g Sensor responses under different driving voltages