A monolithic integrated electro-optical phase modulator, a Mach-Zehnder modulator including one or more of the phase modulators, and method for fabricating the phase modulator by III-V-on-silicon semiconductor processing are provided. The phase modulator includes a silicon-based n-type substrate base layer, and a III-V n-type ridge waveguide for propagating light, wherein the ridge waveguide protrudes from and extends along the n-type substrate base layer. Further, the phase modulator includes one or more insulating layers provided on the ridge waveguide, wherein the one or more insulating layers have together a thickness of 1-100 nm, and a silicon-based p-type top cover layer provided on the one or more insulating layers at least above the ridge waveguide.

An optical phase-shifting device includes a ribbed waveguide portion on an insulating layer, the waveguide portion having a p-n or p-i-n junction extending in a longitudinal direction and having a height. A pair of slab portions are disposed adjacent the waveguide portion, one on each side of the ribbed waveguide portion and on the insulation layer. The slab portion have higher doping concentrations than the respective doping concentrations in the ribbed waveguide portion. At least a portion of each slab portion has a height increasing with distance from the waveguide portion, with the slab height being smaller than that of the waveguide portion at the junction between the waveguide portion and slab portion. A pair of contact portions are formed adjacent the respective slab portion and further away from the waveguide portion. A portion of each contact portion can also have a height varying with distance from the waveguide portion.

The optical modulator includes a lower cladding layer formed on a substrate, a core formed on the lower cladding layer, and an upper cladding layer formed on the core. The core is made of an InP-based semiconductor having a bandgap corresponding to a desired wavelength. Refractive indexes of the lower cladding layer and upper cladding layer are equal to or less than a refractive index of InP.

A photonic integrated circuit comprises a silicon nitride waveguide, an electro-optic modulator formed of a III-nitride waveguide structure disposed on the silicon nitride waveguide, a dielectric cladding covering the silicon nitride waveguide and electro-optic modulator, and electrical contacts disposed on the dielectric cladding and arranged to apply an electric field to the electro-optic modulator.

Methods and systems for a vertical junction high-speed phase modulator are disclosed and may include a semiconductor device having a semiconductor waveguide including a slab section, a rib section extending above the slab section, and raised ridges extending above the slab section on both sides of the rib section. The semiconductor device has a vertical pn junction with p-doped material and n-doped material arranged vertically with respect to each other in the rib and slab sections. The rib section may be either fully n-doped or p-doped in each cross-section along the semiconductor waveguide. Electrical connection to the p-doped and n-doped material may be enabled by forming contacts on the raised ridges, and electrical connection may be provided to the rib section from one of the contacts via periodically arranged sections of the semiconductor waveguide, where a cross-section of both the rib section and the slab section in the periodically arranged sections may be fully n-doped or fully p-doped.

An optoelectronic device, including: a rib waveguide, the rib waveguide including: a ridge portion, which includes a temperature-sensitive optically active region, and a slab portion, positioned adjacent to the ridge portion; the device further comprising a heater, disposed on top of the slab portion wherein a part of the heater closest to ridge portion is at least 2 μm away from the ridge portion. The device may also have a heater provided with a bottom cladding layer, and may also include various thermal insulation enhancing cavities.

A method of forming semiconductor device includes forming an active layer in a substrate including forming components of one or more transistors; forming an MD and gate (MDG) layer over the active layer including forming a gate line; forming a metal-to-S/D (MD) contact structure; and forming a waveguide between the gate line and the MD contact structure; forming a first interconnection layer over the MDG layer including forming a first via contact structure over the gate line; forming a second via contact structure over the MD contact structure; and forming a heater between the first and second via contact structures and over the waveguide.

The optical absorption loss of the optical waveguide and the signal propagation loss of the high-frequency signal electrode are both reduced at a plurality of intersections between the convex optical waveguide and the high-frequency signal electrode, thereby achieving good operating characteristics. An optical waveguide device includes a substrate on which optical waveguides are formed, and an electrode that is formed on the substrate and has intersections crossing over the optical waveguides, in which the optical waveguides are configured by protruding portions extending on the substrate, and an intermediate layer made of a resin is provided at the adjacent intersections along the electrode to fill spaces between the protruding portions along the electrode and covers top of the protruding portions.

A self-lit display panel includes a photonic integrated circuit payer including an array of waveguides and an array of out-couplers for out-coupling portions of the illuminating light through pixels of the panel. The self-lit display panel may include a transparent electronic circuitry layer backlit by the photonic integrated circuit layer; the two layers may be on a same substrate or on opposed substrates defining a cell filled with an electro-active material. The configuration allows for chief ray engineering, zonal illuminating, and separate illumination with red, green, and blue illuminating light.

An optical device including a waveguide and an electrode is described. The waveguide includes at least one optical material having an electro-optic effect. The electrode includes a channel region and extensions protruding from the channel region. The extensions are closer to a portion of the waveguide than the channel region is.