Methods of fabricating optical devices with high refractive index materials are disclosed. The method includes forming a first oxide layer on a substrate and forming a patterned template layer with first and second trenches on the first oxide layer. A material of the patterned template layer has a first refractive index. The method further includes forming a first portion of a waveguide and a first portion of an optical coupler within the first and second trenches, respectively, forming a second portion of the waveguide and a second portion of the optical coupler on a top surface of the patterned template layer, and depositing a cladding layer on the second portions of the waveguide and optical coupler. The waveguide and the optical coupler include materials with a second refractive index that is greater than the first refractive index.

Disclosed herein are configurations and methods to produce very low loss waveguide structures, which can be single-layer or multi-layer. These waveguide structures can be used as a sensing component of a small-footprint integrated optical gyroscope. By using pure fused silica substrates as both top and bottom cladding around a SiN waveguide core, the propagation loss can be well below 0.1 db/meter. Low-loss waveguide-based gyro coils may be patterned in the shape of a spiral (circular or rectangular or any other shape), that may be distributed among one or more of vertical planes to increase the length of the optical path while avoiding the increased loss caused by intersecting waveguides in the state-of-the-art designs. Low-loss adiabatic tapers may be used for a coil formed in a single layer where an output waveguide crosses the turns of the spiraling coil.

Disclosed herein are configurations and methods to produce very low loss waveguide structures, which can be single-layer or multi-layer. These waveguide structures can be used as a sensing component of a small-footprint integrated optical gyroscope. By using pure fused silica substrates as both top and bottom cladding around a SiN waveguide core, the propagation loss can be well below 0.1 db/meter. Low-loss waveguide-based gyro coils may be patterned in the shape of a spiral (circular or rectangular or any other shape), that may be distributed among one or more of vertical planes to increase the length of the optical path while avoiding the increased loss caused by intersecting waveguides in the state-of-the-art designs. Low-loss adiabatic tapers may be used for a coil formed in a single layer where an output waveguide crosses the turns of the spiraling coil.

An optical transceiver including a photonic integrated circuit component, an electric integrated circuit component and an insulating encapsulant is provided. The photonic integrated circuit component includes at least one optical input/output portion and at least one groove located in proximity of the at least one optical input/output portion. The electric integrated circuit component is disposed on and electrically connected to the photonic integrated circuit component. The insulating encapsulant is disposed on the photonic integrated circuit component and laterally encapsulating the electric integrated circuit component. The at least one groove of the photonic integrated circuit component is revealed by the insulating encapsulant and is adapted for insertion of a photonic device.

A plurality of waveguide display substrates, each waveguide display substrate having a cylindrical portion having a diameter and a planar surface, a curved portion opposite the planar surface defining a nonlinear change in thickness across the substrate and having a maximum height D with respect to the cylindrical portion, and a wedge portion between the cylindrical portion and the curved portion defining a linear change in thickness across the substrate and having a maximum height W with respect to the cylindrical portion. A target maximum height D.sub.t of the curved portion is 10.sup.−7 to 10.sup.−6 times the diameter, D is between about 70% and about 130% of D.sub.t, and W is less than about 30% of D.sub.t.

Disclosed herein are configurations and methods to produce very low loss waveguide structures, which can be single-layer or multi-layer. These waveguide structures can be used as a sensing component of a small-footprint integrated optical gyroscope. By using pure fused silica substrates as both top and bottom cladding around a SiN waveguide core, the propagation loss can be well below 0.1 db/meter. Low-loss waveguide-based gyro coils may be patterned in the shape of a spiral (circular or rectangular or any other shape), that may be distributed among one or more of vertical planes to increase the length of the optical path while avoiding the increased loss caused by intersecting waveguides in the state-of-the-art designs. Low-loss adiabatic tapers may be used for a coil formed in a single layer where an output waveguide crosses the turns of the spiraling coil.

A photodiode which includes a core of a first waveguide that terminates in a tapered termination that extends above a core, made of germanium or of SiGe, of a second waveguide, a matching strip that extends opposite the tapered termination on one side and opposite the core of the second waveguide on the opposite side, this matching strip being coupled optically to the core of the second waveguide by an evanescent coupling and including a first zone inside which its effective propagation index is equal to the effective propagation index of a second zone of the tapered termination, these first and second zones optically coupling the tapered termination to the matching strip through a modal coupling, and a low-index layer that extends between the matching strip and the tapered termination.

A plurality of waveguide display substrates, each waveguide display substrate having a cylindrical portion having a diameter and a planar surface, a curved portion opposite the planar surface defining a nonlinear change in thickness across the substrate and having a maximum height D with respect to the cylindrical portion, and a wedge portion between the cylindrical portion and the curved portion defining a linear change in thickness across the substrate and having a maximum height W with respect to the cylindrical portion. A target maximum height D.sub.t of the curved portion is 10.sup.7 to 10.sup.6 times the diameter, D is between about 70% and about 130% of D.sub.t, and W is less than about 30% of D.sub.t.

A method of co-manufacturing silicon waveguides, SiN waveguides, and semiconductor structures in a photonic integrated circuit. A silicon waveguide structure can be formed using a suitable process, after which it is buried in a cladding. The cladding is polished, and a silicon nitride layer is disposed to define a silicon nitride waveguide. The silicon nitride waveguide is buried in a cladding, and annealed. Thereafter, cladding above the silicon waveguide structure can be trenched through, and low-temperature operations can be performed to or with an exposed surface of the silicon waveguide structure.

Disclosed herein are configurations and methods to produce very low loss waveguide structures, which can be single-layer or multi-layer. These waveguide structures can be used as a sensing component of a small-footprint integrated optical gyroscope. By using pure fused silica substrates as both top and bottom cladding around a SiN waveguide core, the propagation loss can be well below 0.1 db/meter. Low-loss waveguide-based gyro coils may be patterned in the shape of a spiral (circular or rectangular or any other shape), that may be distributed among one or more of vertical planes to increase the length of the optical path while avoiding the increased loss caused by intersecting waveguides in the state-of-the-art designs. Low-loss adiabatic tapers may be used for a coil formed in a single layer where an output waveguide crosses the turns of the spiraling coil.