Electro-optical modulating device based on a CMOS-compatible a-Si:H/a-SiCN multistack multistack waveguide

In this paper, we report results on a field-effectinduced light modulation at λ = 1.55 μm in a high-index-contrastwaveguide based on a multisilicon-on-insulator platform. The device is realized with the hydrogenated amorphous silicon (α-Si:H)technology, and it is suitable for monolithic integration in a CMOSIC. The device exploits the free-carrier optical absorption electricallyinduced in the semiconductor core waveguide. The amorphoussilicon waveguiding layer contains several thin dielectricfilms of amorphous silicon carbonitride (α-SiCN) embedded along its thickness, thus highly enhancing the absorbing action of the modulator held in the ON state.