Abstract: A method forms a vertical output coupler for a waveguide, formed of waveguide material and disposed within a layer stack on a top surface of a wafer. The method includes etching through a portion of the wafer to form a via that exposes the waveguide material, and etching the waveguide material to remove at least a first portion of the waveguide. The etching forms a tilted plane in the waveguide material. The method further includes coating the first tilted plane with one or more reflective layers, to form a tilted mirror in contact with the first tilted plane in the waveguide material. The tilted mirror forms the vertical output coupler such that light propagating through the waveguide is deflected by the tilted mirror, and exits the waveguide.

Abstract: A method forms a vertical output coupler for a waveguide that propagates light along a horizontal propagation direction, through a waveguide material that overlies a buried oxide layer. The method includes etching the waveguide to remove a portion of the waveguide. The etching forms at least a first plane that is at an edge of the waveguide, is adjacent to the removed portion of the waveguide, and is tilted at a vertical angle between 20 degrees and 70 degrees with respect to the propagation direction. The method further includes coating the first tilted plane with a reflective metal to form a mirror, such that the mirror reflects the light into a direction having a vertical component.

Abstract: A method of fabricating a waveguide mode expander includes providing a substrate including a waveguide, bonding a chiplet including multiple optical material layers in a mounting region adjacent an output end of the waveguide, and selectively removing portions of the chiplet to form tapered stages that successively increase in number and lateral size from a proximal end to a distal end of the chiplet. The first optical material layer supports an input mode substantially the same size as a mode exiting the waveguide. One or more of the overlying layers, when combined with the first layer, support a larger, output optical mode size. Each tapered stage of the mode expander is formed of a portion of a respective layer of the chiplet. The first layer and the tapered stages form a waveguide mode expander that expands an optical mode of light traversing the chiplet.

Abstract: A transfer substrate with a compliant resin is used to bond one or more chips to a target wafer. An implant region is formed in a transfer substrate. A portion of the transfer substrate is etched to form a riser. Compliant material is applied to the transfer substrate. A chip is secured to the compliant material, wherein the chip is secured to the compliant material above the riser. The chip is bonded to a target wafer while the chip is secured to the compliant material. The transfer substrate and compliant material are removed from the chip. The transfer substrate is opaque to UV light.

Abstract: An optical modulator includes a splitter, phase modulators, amplitude modulators, intensity modulators, and a combiner. The splitter is configured to receive light, and split the light into portions of the light. Each of the phase modulators is configured to receive a corresponding one of the portions of the light, and modulate a phase of the portion of the light to provide a phase-modulated signal. Each of the amplitude modulators is configured to receive a corresponding one of the phase-modulated signals, and modulate an amplitude of the phase-modulated signal to provide an amplitude-modulated signal. Each of the intensity modulators is configured to receive a corresponding one of the amplitude-modulated signals, and modulate an intensity of the amplitude-modulated signals to provide an intensity-modulated signal. The combiner is configured to receive the intensity-modulated signals, combine the intensity-modulated signals into a combined signal, and output the combined signal.

Abstract: Micro pillars are formed in silicon. The micro pillars are used in boding the silicon to hetero-material such as III-V material, ceramics, or metals. In bonding the silicon to the hetero-material, indium is used as a bonding material and attached to the hetero-material. The bonding material is heated and the silicon and the hetero-material are pressed together. As the silicon and the hetero-material are pressed together, the micro pillars puncture the bonding material. In some embodiments, pedestals are used in the silicon as hard stops to align the hetero-material with the silicon.

Abstract: A transfer substrate with a compliant resin is used to bond one or more chips to a target wafer. An implant region is formed in a transfer substrate. A portion of the transfer substrate is etched to form a riser. Compliant material is applied to the transfer substrate. A chip is secured to the compliant material, wherein the chip is secured to the compliant material above the riser. The chip is bonded to a target wafer while the chip is secured to the compliant material. The transfer substrate and compliant material are removed from the chip. The transfer substrate is opaque to UV light.

Abstract: A waveguide mode expander couples a smaller optical mode in a semiconductor waveguide to a larger optical mode in an optical fiber. The waveguide mode expander comprises a shoulder made of crystalline silicon and a ridge made of non-crystalline silicon (e.g., amorphous silicon). In some embodiments, the ridge of the waveguide mode expander has a plurality of stages, the plurality of stages have different widths and/or thicknesses at a given cross section.

Abstract: A waveguide mode expander couples a smaller optical mode in a semiconductor waveguide to a larger optical mode in an optical fiber. The waveguide mode expander comprises a shoulder and a ridge. In some embodiments, the ridge of the waveguide mode expander has a plurality of stages, the plurality of stages having different widths at a given cross section.

Abstract: A monolithic photonic integrated circuit (PIC) chip where the active waveguide cores of the modulated sources of the PIC are multiple quantum wells (MQWs) and the passive waveguide cores of an optical combiner are a bulk layer or material. The cores of the waveguide cores may be a quaternary such as InGaAsP or InAlGaAs.

Abstract: A photonic integrated circuit (PIC) chip comprising an array of modulated sources, each providing a modulated signal output at a channel wavelength different from the channel wavelength of other modulated sources and a wavelength selective combiner having an input optically coupled to received all the signal outputs from the modulated sources and provide a combined output signal on an output waveguide from the chip. The modulated sources, combiner and output waveguide are all integrated on the same chip.

Abstract: A monolithic photonic integrated circuit (PIC) chip where the active waveguide cores of the modulated sources of the PIC are multiple quantum wells (MQWs) and the passive waveguide cores of an optical combiner are a bulk layer or material. The cores of the waveguide cores may be a quaternary such as InGaAsP or InAlGaAs.

Abstract: A monolithic photonic integrated circuit (PIC) chip comprises an array of modulated sources providing a plurality of channel signals of different wavelengths and an optical combiner coupled to receive the channel signals and produce a combined output of the channel signals. The arrays of modulated sources are formed as ridge waveguides to enhance the output power from the respective modulated sources so that the average output power from the sources is approximately 2 to 4 times higher than in the case of comparable arrays of modulated sources formed as buried waveguides.

Abstract: A monolithic photonic integrated circuit (PIC) chip comprises an array of modulated sources providing a plurality of channel signals of different wavelengths and an optical combiner coupled to receive the channel signals and produce a combined output of the channel signals. The arrays of modulated sources are formed as ridge waveguides to enhance the output power from the respective modulated sources so that the average output power from the sources is approximately 2 to 4 times higher than in the case of comparable arrays of modulated sources formed as buried waveguides.