A Sensitivity-Enhanced Electric Field Sensor with Electrostatic Field Bias

An electrostatic field biased cantilever electric field sensor with sensitivity improvement is proposed in this paper. Theoretically, the sensitivity of the sensor is proportional to the applied electrostatic field strength. A demonstrated sensor is developed, which consists of a Silicon cantilever coated with an Aluminum Nitride (AlN) piezoelectric film for signal readout, and a PTFE electret layer for electrostatic field bias. When the surface potential of the electret layer is -683 V, the sensitivity of the cantilever electric field sensor reaches 15.8 mV/(kV/m), and the resolution is about 20 V/m.