Different electro-optical modulator designs based on electromagnetically induced transparency are proposed. A conductor–gap–silicon input waveguide is coupled to microrings-on-disks on each side. A low voltage modulating signal is applied to the modulator in a push-pull configuration, which changes the refractive index of the embedded layer of the electro-optical polymer. The proposed microrings-on-disks and cascaded microring modulators with submicron radii can efficiently modulate the light wave with moderate propagation losses. The microring-on-disk modulator achieved ultrasmall capacitance, 1.06 fF, and low power consumption, 2.12  fJ/bit. Both modulators have low insertion losses and high extinction ratios.