A novel electric field microsensor with low cross-axis coupling interference

One of the major concerns in developing three-dimensional (3D) electric field sensor (EFS) is its susceptibility to cross-axis coupling interference. The output signal for each sensing axis of a 3D EFS is properly coupled by electric field components from other two orthogonal sensing axes. In this paper, a novel electric field microsensor with low cross-axis coupling interference is presented. The microsensor chip contains a pair of symmetrically located in-plane differential sensing structures, which makes the microsensor chip capable of sensing in-plane electric field parallel to sensing structures and reducing cross-axis coupling interference. Therefore, a 3D EFS with low cross-axis coupling interference can be realized with three microsensor chips. Simulation results show that the outputs of the 3D EFS are in good accordance with electric field components along its sensing axes without coupling interference. Experiments have proved that the microsensor chip is capable of measuring the electric field component along its sensing axis.