Hybrid eo polymer modulator with silicon photonics

An EO polymer Mach-Zehnder modulator comprising:

• a substrate with a cladding layer formed on the surface;
• a passive waveguide core including an input waveguide, and an output waveguide connected at opposite ends to spaced apart parallel legs, each of the legs having a common cross-sectional area, the passive waveguide core formed in the cladding layer and each leg including an elongated tapered active section;
• elongated strips of EO polymer, the elongated strips of EO polymer positioned between and parallel with the electrodes and coplanar with the electrodes;
• elongated spaced apart, parallel trenches in the cladding layer and/or in an upper surface of the elongated strips of EO polymer, the elongated tapered active sections of the waveguide core positioned in the elongated trenches;
• electrodes positioned on a surface of the cladding layer on opposite sides of each of the elongated trenches;
• and
• the elongated strips of EO polymer overlying each of the elongated tapered active sections of the waveguide core.

A method of fabricating an EO polymer modulator comprising the steps of:

• providing a substrate with a cladding layer formed on the surface;
• forming an elongated trench in the cladding layer;
• providing a passive waveguide core, having a cross-sectional area, in the cladding layer and including an elongated tapered active section, the elongated tapered active section of the waveguide core positioned in the elongated trench;
• depositing elongated strips of auxiliary metal on the surface of the cladding layer on opposite sides of the elongated trench, parallel with and spaced from the elongated trench;
• depositing elongated strips of electrically conductive material on the surface of the cladding layer adjacent to and parallel with outer surfaces of the auxiliary metal elongated strips;
• depositing a layer of EO polymer material over the elongated trench, the elongated strips of auxiliary metal, and the elongated strips of electrically conductive material, the elongated strips of EO polymer positioned between and parallel with the electrodes and coplanar with the electrodes;
• applying an electric field across the elongated strips of auxiliary metal while simultaneous heating the structure to a critical temperature to align permanent dipole chromophore molecules in the EO layer;
• removing a portion of the EO polymer layer overlying the elongated strips of auxiliary metal to expose an upper surface of the elongated strips of auxiliary metal;
• removing the exposed elongated strips of auxiliary metal to form trenches between the elongated strips of electrically conductive material and the EO polymer material;
• depositing a layer of low refractive index material, with a refractive index lower than a refractive index of the EO polymer material, over the elongated strips of electrically conductive material and the EO polymer layer.