A high sensitivity SOI electric-field sensor with novel comb-shaped microelectrodes

We have developed a highly sensitive electric-field sensor with novel comb-shaped microelectrodes. The sensor is based on modulating an incident field with a grounded shutter and measuring the induced charge of sensing electrodes. Owing to the shutter covering the side wall of the sensing electrodes, the fringing fields are no longer a factor that reduces the performance of the sensor. Moreover, in order to improve the efficiency of the charge induction, comb-shaped microelectrodes are introduced. The sensor can measure not only electrostatic field, but also AC field. Tested in ambient air conditions, the minimum detectable field of the sensor is approximately 40V/m with an uncertainty of 1% in DC electric field range 0-50kV/m and 10V/m for a 50Hz AC field. Finally, the use of the sensor to detect ice accretion on high power electric cables is achieved.