An electrostatic field sensor driven by self-excited vibration of sensor/actuator integrated piezoelectric micro cantilever

We have developed MEMS-based electrostatic field sensors (MEMS-EFS), which integrate a probe to detect electrostatic field and Pb(Zr, Ti)O3 (PZT) thin films for sensor and actuator into micro cantilevers. The MEMS-EFS were fabricated through sol-gel deposition of PZT thin films and MEMS microfabrication process. Self-excited vibration of the micro cantilevers has been achieved by amplifying and forwarding the output voltage from the PZT thin films for sensor with a band-pass filter circuit. The developed MEMS-EFS can evaluate an electrostatic field of -3 to 3 kV with good linearity.