Embodiments are disclosed for a coupling element with embedded modal filtering for a laser and/or a photodiode. An example system includes a laser and an optical coupling element. The laser is configured to emit an optical signal. The optical coupling element is configured to receive the optical signal emitted by the laser. The optical coupling element is also configured to be connected to an optical fiber such that, in operation, the optical signal is transmitted from the laser to the optical fiber via the optical coupling element. Furthermore, the coupling element comprises a tapered section that provides modal filtering of the optical signal.

An optical device is disclosed, including a phase delay, a first adiabatic coupler adapted to receive an input signal and adapted to be optically coupled to an input of the phase delay, and a second adiabatic coupler adapted to be optically coupled to an output of the phase delay. The second adiabatic coupler includes a first waveguide including a first portion optically coupled to the first output and including a first width, and a second waveguide including a second portion optically coupled to the second output and including a second width that is approximately equal to the first width.

Structures for a photodetector or terminator and methods of fabricating a structure for a photodetector or terminator. The structure includes a waveguide core, a light-absorbing layer having a sidewall, and a taper positioned adjacent to the sidewall of the light-absorbing layer. The taper extends laterally from the sidewall of the light-absorbing layer to overlap with the waveguide core, and the taper has a thickness that varies with position relative to the sidewall of the light-absorbing layer. For example, the thickness of the taper may decrease with increasing distance from the sidewall of the light-absorbing layer.

An optical multiplexer. The optical multiplexer comprising: a plurality of input waveguides, each comprising an input slab portion and an input rib portion; an output waveguide, comprising an output slab portion and output rib portion; and a wavelength multiplexer element, coupled to each input waveguide and the output waveguide, the wavelength multiplexer element comprising a slab waveguide which includes a grating configured to multiplex signals of differing wavelengths, received from the input waveguides, into a multiplexed signal, and provide the multiplexed signal to the output waveguide. The input rib portion(s) of one or more of the input waveguides are tapered so as to decrease in width in a direction towards the slab waveguide of the wavelength multiplexer element which is an echelle grating or an arrayed waveguide grating.

In integrated optical structures (e.g., silicon-to-silicon-nitride mode converters) implemented in semiconductor-on-insulator substrates, wire waveguides whose sidewalls substantially consist of portions coinciding with crystallographic planes and do not extend laterally beyond the top surface of the wire waveguide may provide benefits in performance and/or manufacturing needs. Such wire waveguides may be manufactured, e.g., using a dry-etch of the semiconductor device layer down to the insulator layer to form a wire waveguide with exposed sidewalls, followed by a smoothing crystallographic wet etch.

Provided here are: a semiconductor laser section formed on a surface of a semiconductor substrate; a spot-size converter section in which an optical waveguide having a core layer for propagating laser light emitted from the semiconductor laser section is provided; and a monitor PD section which is provided on the spot-size converter section laterally with respect to a propagation direction of the laser light; wherein, the regions of a PD anode electrode and a PD cathode electrode in the monitor PD section are partially opposed to each other through an insulating film, so that the surge breakdown voltage of the monitor PD section is increased.

A semiconductor device is provided. The semiconductor device includes a waveguide over a substrate. The semiconductor device includes a first dielectric structure over the substrate, wherein a portion of the waveguide is in the first dielectric structure. The semiconductor device includes a second dielectric structure under the waveguide, wherein a first sidewall of the second dielectric structure is adjacent a first sidewall of the substrate.

Structures for a polarization rotator and methods of fabricating a structure for a polarization rotator. The structure includes a substrate, a first waveguide core over the substrate, and a second waveguide core over the substrate. The second waveguide core is positioned proximate to the section of the first waveguide core. The second waveguide core is comprised of a material having a refractive index that is reversibly variable in response to a stimulus.

An integrated optical device fabricated in the back end of line process located within the vertical span of the metal stack and having one or more advantages over a corresponding integrated optical device fabricated in the silicon on insulator layer.

The present disclosure provides a semiconductor device package. The semiconductor device package includes a semiconductor substrate having a first surface and a first optical coupler disposed on the first surface of the semiconductor substrate. The first optical coupler includes a first surface facing away from the first surface of the semiconductor substrate and a first lateral surface connected to the first surface of the first optical coupler. The first surface of the first optical coupler and the first lateral surface of the optical coupler define an angle greater than 90 degrees. A method of manufacturing a semiconductor device package is also disclosed.