Abstract: Structures for a waveguide escalator, as well as methods of forming such structures. The structure comprises a first waveguide core on a substrate, a second waveguide core, and a back-end-of-line stack including a third waveguide core disposed between the first waveguide core and the second waveguide core. The third waveguide core comprises a layer stack that includes a first layer, a second layer, and a third layer between the first layer and the second layer. The first layer and the second layer comprise a first dielectric material with a first refractive index, and the third layer comprises a second dielectric material with a second refractive index that is less than the first refractive index.

Abstract: Structures for an optical switch and methods of forming such structures. The structure comprises a first waveguide core including a first portion and a second portion, a second waveguide core including a first portion and a second portion, a ring resonator having a first portion adjacent to the first portion of the first waveguide core and a second portion adjacent to the first portion of the second waveguide core, and an optical coupler coupled to the second portion of first waveguide core and the second portion of the second waveguide core. The first portion of the ring resonator is spaced from the first portion of the first waveguide core by a first gap over a first light coupling region, and the second portion of the ring resonator is spaced from the first portion of the second waveguide core by a second gap over a second light coupling region.

Abstract: Structures including an electro-absorption modulator and methods of forming such structures. The structure comprises a waveguide core including a first tapered section, a second tapered section, and a longitudinal axis. The first tapered section and the second tapered section are aligned along the longitudinal axis. The structure further comprises a first waveguide taper overlapping the first tapered section of the waveguide core, a second waveguide taper overlapping the second tapered section of the waveguide core, and a multiple-layer structure on the waveguide core between the first waveguide taper and the second waveguide taper.

Abstract: Structures for a power splitter that include a multimode interference coupler and methods of forming such structures. The structure comprises a multimode interference coupler including a grating having a plurality of grating lines, an input waveguide core, and an output waveguide core. The grating lines are disposed between the input waveguide core and the output waveguide core. The structure further comprises a resistive heating element adjacent to the grating lines.

Abstract: Disclosed is a thermal stabilization circuit including a heater, which is adjacent and thermally coupled to a closed-curve waveguide of an optical ring resonator, and an analog feedback circuit, which includes a fully autonomous analog feedback loop from a drop port of a bus waveguide of the optical ring resonator to the heater. This analog feedback circuit is configured to dynamically control the electrical power provided to the heater and, thereby to dynamically control the thermal output of the heater in order to tune the ring resonance wavelength to the operating laser wavelength. The analog feedback circuit is further configured to be independent of input power, to be power efficient, to have a relatively small footprint, to have a tunable time constant and to facilitate adjustable wavelength locking. Also disclosed is a device (e.g., a ring-based transceiver or the like), which includes multiple optical ring resonators and corresponding thermal stabilization circuits.

Abstract: Structures for a broadband optical switch and methods of forming such structures. The structure comprises a Mach-Zehnder interferometer including first and second arms. The first arm comprises a first waveguide core, and the second arm comprises a second waveguide core. The structure further comprises a ring resonator comprising a third waveguide core that has a first thickness. A portion of the third waveguide core is adjacent to a portion of the first waveguide core over a light coupling region. A slab layer connects the portion of the first waveguide core to the portion of the third waveguide core. The slab layer has a second thickness that is less than the first thickness of the first waveguide core.

Abstract: Structures for a thermo-optic phase shifter and methods of forming a thermo-optic phase shifter. The structure comprises an interconnect structure including a dielectric layer, a waveguide core on the dielectric layer, and a heater on the dielectric layer. The heater includes a resistive heating element positioned adjacent to the waveguide core.

Abstract: Structures including stacked photonics chips and methods of fabricating a structure including stacked photonics chips. The structure comprises a first chip including a first waveguide core, a ring resonator adjacent to a portion of the first waveguide core, and a first dielectric layer over the first waveguide core and the ring resonator. The first dielectric layer has a first surface. The structure further comprises a second chip including a second waveguide core and a second dielectric layer over the second waveguide core. The second dielectric layer has a second surface adjacent to the first surface of the first dielectric layer, and the second waveguide core is positioned adjacent to the ring resonator.

Abstract: Structures including an electro-absorption modulator and methods of forming such structures. The structure comprises a waveguide core including a first tapered section, a second tapered section, and a longitudinal axis. The first tapered section and the second tapered section are aligned along the longitudinal axis. The structure further comprises a first waveguide taper overlapping the first tapered section of the waveguide core, a second waveguide taper overlapping the second tapered section of the waveguide core, and a multiple-layer structure on the waveguide core between the first waveguide taper and the second waveguide taper.

Abstract: The present disclosure generally relates to semiconductor devices for use in optoelectronic/photonic applications and integrated circuit (IC) chips. More particularly, the present disclosure relates to semiconductor devices having a reflector and a photonic component and a method of forming the same. The present disclosure provides a semiconductor device having a substrate, a photonic component arranged above the substrate, a bottom reflector arranged above the substrate and positioned below the photonic component, in which the bottom reflector has a plurality of grating structures configured to reflect electromagnetic waves towards the photonic component, and a top reflector arranged above the photonic component, in which the top reflector has a plurality of grating structures configured to reflect electromagnetic waves towards the photonic component.

Abstract: Structures including stacked photonics chips and methods of fabricating a structure including stacked photonics chips. The structure comprises a first chip including a first waveguide core, a ring resonator adjacent to a portion of the first waveguide core, and a first dielectric layer over the first waveguide core and the ring resonator. The first dielectric layer has a first surface. The structure further comprises a second chip including a second waveguide core and a second dielectric layer over the second waveguide core. The second dielectric layer has a second surface adjacent to the first surface of the first dielectric layer, and the second waveguide core is positioned adjacent to the ring resonator.

Abstract: A laser structure, including: a dielectric matrix formed of a first material; a laser source formed within the dielectric matrix and formed of a semiconductor material; and a plurality of side confining features formed within the dielectric matrix and extending parallel to and along a length of the laser source. The plurality of side confining features are formed of the semiconductor material.

Abstract: Disclosed is a photonic structure and associated method. The structure includes a closed-curve waveguide having a first height, as measured from the top surface of an insulator layer, and an outer curved sidewall that extends essentially vertically the full first height (e.g., to minimize signal loss). The structure includes a closed-curve thermal coupler and a heating element. The closed-curve thermal coupler is thermally coupled to and laterally surrounded by the closed-curve waveguide and has a second height that is less than the first height. In some embodiments, the closed-curve waveguide and the closed-curve thermal coupler are continuous portions of the same semiconductor layer having different thicknesses. The heating element is thermally coupled to the closed-curve thermal coupler and thereby indirectly thermally coupled to the closed-curve waveguide.

Abstract: Disclosed is a thermal stabilization circuit including a heater, which is adjacent and thermally coupled to a closed-curve waveguide of an optical ring resonator, and an analog feedback circuit, which includes a fully autonomous analog feedback loop from a drop port of a bus waveguide of the optical ring resonator to the heater. This analog feedback circuit is configured to dynamically control the electrical power provided to the heater and, thereby to dynamically control the thermal output of the heater in order to tune the ring resonance wavelength to the operating laser wavelength. The analog feedback circuit is further configured to be independent of input power, to be power efficient, to have a relatively small footprint, to have a tunable time constant and to facilitate adjustable wavelength locking. Also disclosed is a device (e.g., a ring-based transceiver or the like), which includes multiple optical ring resonators and corresponding thermal stabilization circuits.

Abstract: Disclosed is a structure (e.g., a lab-on-chip structure) including a substrate, an insulator layer on the substrate, and at least one optical ring resonator. Each ring resonator includes cladding material on the insulator layer and, embedded within the cladding material, a first waveguide core with an input and an output, and second waveguide core(s) (e.g., ring waveguide core(s)) positioned laterally adjacent to the first waveguide core. A reservoir is below the ring resonator within the insulator layer and substrate such that surfaces of the waveguide cores are exposed within the reservoir. During a sensing operation, the waveguide core surfaces contact with fluid within the reservoir and a light signal at the output of the first waveguide core is monitored (e.g., by a sensing circuit, which in some embodiments is also coupled to a reference optical ring resonator) and used, for example, for spectrum-based target identification and, optionally, characterization.

Abstract: Disclosed is a structure (e.g., a lab-on-chip structure) including a substrate, an insulator layer on the substrate, and at least one optical ring resonator. Each ring resonator includes cladding material on the insulator layer and, embedded within the cladding material, a first waveguide core with an input and an output, and second waveguide core(s) (e.g., ring waveguide core(s)) positioned laterally adjacent to the first waveguide core. A reservoir is below the ring resonator within the insulator layer and substrate such that surfaces of the waveguide cores are exposed within the reservoir. During a sensing operation, the waveguide core surfaces contact with fluid within the reservoir and a light signal at the output of the first waveguide core is monitored (e.g., by a sensing circuit, which in some embodiments is also coupled to a reference optical ring resonator) and used, for example, for spectrum-based target identification and, optionally, characterization.

Abstract: Embodiments of the disclosure provide a photonic integrated circuit (PIC) structure with a passage for a waveguide through a barrier structure. The PIC structure includes a barrier structure on a substrate, having a first sidewall and a second sidewall opposite the first sidewall. A passage is within the barrier structure, and extends from a first end at the first sidewall of the barrier structure to a second end at the second sidewall of the barrier structure. A shape of the passage includes a reversal segment between the first end and the second end. A waveguide within the passage and extends from the first end to the second end of the barrier structure.

Abstract: Structures for an optical power modulator and methods of fabricating a structure for an optical power modulator. A first waveguide core includes first and second sections. A second waveguide core includes a first section laterally adjacent to the first section of the first waveguide core and a second section laterally adjacent to the second section of the first waveguide core. An interconnect structure is formed over the first waveguide core and the second waveguide core. The interconnect structure includes first and second transmission lines. The first transmission line is physically connected within the interconnect structure to the first section of the first waveguide core. The second transmission line includes a first section physically connected within the interconnect structure to the second section of the first waveguide core and a second section adjacent to the first transmission line.

Abstract: Embodiments of the disclosure provide an optical ring modulator. The optical ring modulator includes waveguide with a first semiconductor material of a first doping type, and a second semiconductor material having a second doping type adjacent the first semiconductor material. A P-N junction is between the first semiconductor material and the second semiconductor material. A plurality of photonic crystal layers, each embedded within the first semiconductor material or the second semiconductor material, has an upper surface that is substantially coplanar with an upper surface of the waveguide structure.

Abstract: Disclosed is a photonic structure and associated method. The structure includes a closed-curve waveguide having a first height, as measured from the top surface of an insulator layer, and an outer curved sidewall that extends essentially vertically the full first height (e.g., to minimize signal loss). The structure includes a closed-curve thermal coupler and a heating element. The closed-curve thermal coupler is thermally coupled to and laterally surrounded by the closed-curve waveguide and has a second height that is less than the first height. In some embodiments, the closed-curve waveguide and the closed-curve thermal coupler are continuous portions of the same semiconductor layer having different thicknesses. The heating element is thermally coupled to the closed-curve thermal coupler and thereby indirectly thermally coupled to the closed-curve waveguide.