An electric field sensor includes a substrate having a low resistive semiconductor layer doped with a high-density dopant as the top layer of the substrate, a high resistive semiconductor layer doped with a low-density dopant, the high resistive semiconductor layer located at a partial area on the low resistive semiconductor layer, and a conductive layer located on the high resistive semiconductor layer, wherein a change of an electric field is detected by a change of a current flowing through the low resistive semiconductor layer, the high resistive semiconductor layer, and the conductive layer.