In some implementations, a photonic transmission structure includes a first cladding structure; a first active structure disposed over the first cladding structure; and a second cladding structure disposed over the first active structure. The first active structure includes a non-alkali, oxide solution that includes a cation that is niobium.

A method of manufacturing an optical waveguide with a vertical slot including the steps of a) providing a substrate successively including an electric insulator layer and a crystalline semiconductor layer, b) forming a trench on the semiconductor layer to expose the electric insulator layer and defining first and second semiconductor areas on either side, step b) being executed so that the first semiconductor area has a lateral edge extending across the entire thickness of the semiconductor layer, c) forming the dielectric layer having the predetermined width across the entire thickness of the lateral edge, the method being remarkable in that the trench formed at step b) is configured so that the second semiconductor area forms a seed layer.

A method of fabricating a heterogeneous semiconductor wafer includes depositing a III-V type semiconductor epitaxial layer on a first wafer having a semiconductor substrate. The first wafer is then bonded to a second wafer having a patterned silicon layer formed on a semiconductor substrate, wherein the III-V type semiconductor epitaxial layer is bonded to the patterned silicon layer of the second wafer. The semiconductor substrate associated with the first wafer is removed to expose the III-V type semiconductor epitaxial layer.

A method for producing a waveguide including a germanium-based core and a cladding is provided, the method including a step of “low temperature” depositing of a shell after forming the core by engraving, such that the deposition temperature is less than 780° C., followed by a step of “high temperature” depositing of a thick encapsulation layer. The shell and the encapsulation layer at least partially form the cladding of the waveguide. Optionally, a step of annealing under hydrogen at a “low temperature”, less than 750° C., precedes the deposition of the shell. These “low temperature” annealing and depositing steps advantageously make it possible to avoid a post-engraving alteration of the free surfaces of the core during the forming of the cladding which is less germanium-rich.

Various embodiments provide for systems and techniques for the successful fabrication of metal oxide (TMO)-on-glass layer stacks via direct deposition. The resulting samples feature epitaxial, strontium titanate (STO) or barium titanate (BTO) films on silicon dioxide (SiO.sub.2) layers, forming STO- or BTO-buffered SiO.sub.2 pseudo-substrates. As the integration of TMO films on silicon rely on an STO or BTO buffer layer, a wide variety of TMO-based integrated devices (e.g., circuits, waveguides, etc.) can be fabricated from the TMO-on-glass platform of the present technology. Moreover, the STO, or the BTO, survives the fabrication process without a corresponding degradation of crystalline quality, as evidenced by various objective measures.

Two semiconductor chips are optically aligned to form a hybrid semiconductor device. Both chips have optical waveguides and alignment surface positioned at precisely-defined complementary vertical offsets from optical axes of the corresponding waveguides, so that the waveguides are vertically aligned when one of the chips is placed atop the other with their alignment surface abutting each other. The position of the at least one of the alignment surface in a layer stack of its chip is precisely defined by epitaxy. The chips are bonded at offset bonding pads with the alignment surfaces abutting in the absence of bonding material therebetween.

Embodiments herein relate to photonic integrated circuits with an on-chip optical isolator. A photonic transmitter chip may include a laser and an on-chip isolator optically coupled with the laser that includes an optical waveguide having a section coupled with a magneto-optic liquid phase epitaxy grown garnet film. In some embodiments, a cladding may be coupled with the garnet film, the on-chip isolator may be arranged in a Mach-Zehnder interferometer configuration, the waveguide may include one or more polarization rotators, and/or the garnet film may be formed of a material from a rare-earth garnet family. Other embodiments may be described and/or claimed.

An integrated circuit optical backplane die and associated semiconductor fabrication process are described for forming optical backplane mirror structures for perpendicularly deflecting optical signals out of the plane of the optical backplane die by selectively etching an optical waveguide semiconductor layer (103) on an optical backplane die wafer using an orientation-dependent anisotropic wet etch process to form a first recess opening (107) with angled semiconductor sidewall surfaces (106) on the optical waveguide semiconductor layer, where the angled semiconductor sidewall surfaces (106) are processed to form an optical backplane mirror (116) for perpendicularly deflecting optical signals to and from a lateral plane of the optical waveguide semiconductor layer.

A silicon photonic chip is provided comprising a top silicon device layer; an insulating layer beneath the top silicon device layer; an intermediate silicon device layer beneath the insulating layer; a further insulating layer beneath the intermediate silicon device layer; a silicon substrate beneath the further insulating layer; and a first silicon waveguide, the first silicon waveguide being partially formed by a portion of the intermediate silicon device layer.

A low voltage APD is disposed at an end of a waveguide extending laterally within a silicon device layer of a PIC chip. The APD is disposed over an inverted re-entrant mirror co-located at the end of the waveguide to couple light by internal reflection from the waveguide to an under side of the APD. In exemplary embodiments, a 45°-55° facet is formed in the silicon device layer by crystallographic etch. In embodiments, the APD includes a silicon multiplication layer, a germanium absorption layer over the multiplication layer, and a plurality of ohmic contacts disposed over the absorption layer. An overlying optically reflective metal film interconnects the plurality of ohmic contacts and returns light transmitted around the ohmic contacts to the absorption layer for greater detector responsivity.