ELECTRO-OPTICAL MODULATOR USING RIBBED WAVEGUIDES

摘要

An optical modulator may include a lower waveguide, an upper waveguide, and a dielectric layer disposed therebetween. When a voltage potential is created between the lower and upper waveguides, these layers form a silicon-insulator-silicon capacitor (also referred to as SISCAP) guide that provides efficient, high-speed optical modulation of an optical signal passing through the modulator. In one embodiment, at least one of the waveguides includes a respective ridge portion aligned at a charge modulation region which may aid in confining the optical mode laterally (e.g., in the width direction) in the optical modulator. In another embodiment, ridge portions may be formed on both the lower and the upper waveguides. These ridge portions may be aligned in a vertical direction (e.g., a thickness direction) so that ridges overlap which may further improve optical efficiency by centering an optical mode in the charge modulation region.

主权项

1. An optical device, comprising:
a first silicon waveguide disposed on a dielectric substrate, the first silicon waveguide comprising a first ridge extending in a direction of an optical path; a dielectric layer having a lower surface disposed on an upper surface of the first ridge; a second silicon waveguide disposed on an upper surface of the dielectric layer opposite the lower surface of the dielectric layer, the second silicon waveguide comprising a second ridge extending in a direction of the optical path, wherein the second ridge at least partially overlaps both the dielectric layer and the first ridge, and wherein the first silicon waveguide is doped a first conductivity type and the second silicon waveguide is doped a second, different conductivity type; a first electrical contact coupled to the first silicon waveguide; and a second electrical contact coupled to the second silicon waveguide.