A light controlled semiconductor switch (LCSS), method of making, and method of using are provided. In embodiments, a vertical LCSS includes: a semiconductor body including a photoactive layer of gallium nitride (GaN) doped with carbon; a first electrode in contact with a first surface of the semiconductor body, the first electrode defining an area through which light energy from at least one light source can impinge on the first surface; and a second electrode in contact with a second surface of the semiconductor body opposed to the first surface, wherein the vertical LCSS is configured to switch from a non-conductive off-state to a conductive on-state when the light energy impinging on the semiconductor body is sufficient to raise electrons within the photoactive layer into a conduction band of the photoactive layer.

A method for the fabrication of avalanche photodiodes (APDs) useful as high-sensitivity Geiger-mode APDs. The photodetector is formed on a semiconductor substrate of indium phosphide (InP) having epitaxial layers, including indium gallium arsenide (InGaAs) as the photodetecting layer, with n-doped InP to one side, and layers of InP incorporating p-doped regions on the opposite side. The p-doped regions serve to define an array of micro-cells, which may have a hexagonal configuration. A well may be etched through the epitaxial structures, allowing one electrode to contact the n-doped InP layer and another electrode to contact the p-doped InP regions, with both electrodes on the same side of the detector. Bonding techniques then attach the semiconductor wafer to a support substrate, which may additionally be configured with electronic circuitry positioned to electrically contact the electrodes on the semiconductor wafer surface, and diced to form individual devices.

Methods and apparatus for processing a photonic device are provided herein. For example, methods include etching, using a plasma etch process that uses a first gas, a first epitaxial layer of material of the photonic device comprising a base layer comprising at least one of silicon, germanium, sapphire, aluminum indium gallium arsenide (Al.sub.xIn.sub.yGa.sub.1-x-yAs), aluminum indium gallium phosphide (Al.sub.xIn.sub.yGa.sub.1-x-yP), aluminum indium gallium nitride (Al.sub.xIn.sub.yGa.sub.1-x-yN), aluminum indium gallium arsenide phosphide (Al.sub.xIn.sub.yGa.sub.1-x-yAs.sub.zP.sub.1-z), depositing, using a plasma deposition process that uses a second gas different from the first gas, a first dielectric layer over etched sidewalls of the first epitaxial layer of material, etching, using the first gas, a second epitaxial layer of material of the photonic device, and depositing, using the second gas, a second dielectric layer over etched sidewalls of the second epitaxial layer of material.

A bonded semiconductor light-receiving device including an epitaxial layer to serve as a device-functional layer, and a support substrate made of a material different from that of the device-functional layer and bonded to the epitaxial layer via a bonding material layer. The device-functional layer has a bonding surface with an uneven pattern formed thereon.

A light controlled semiconductor switch (LCSS), method of making, and method of using are provided. In embodiments, a lateral LCSS includes: a semiconductor body including a photoactive layer of gallium nitride (GaN) doped with carbon; a first electrode in contact with a first surface of the semiconductor body; and a second electrode in contact with the first surface of the semiconductor body, the first and second electrodes defining an area through which light energy from at least one light source can impinge on the first surface, wherein the LCSS is configured to switch from a non-conductive off-state to a conductive on-state when the light energy impinging on the semiconductor body is sufficient to raise electrons within the photoactive layer into a conduction band of the photoactive layer.

Example methods, compositions and structures are presented whereby sub-10-nm-thick strain-relieving Si.sub.1-xGe.sub.x layers can be realized by Ge ion implantation, into, and selective oxidation of, Si(111) wafers. The resulting Ge-rich layers are fully strain relaxed via a network of misfit dislocations at the Si/Si.sub.1-xGe, interface, which do not propagate through the Si.sub.1-xGe.sub.x film. The dislocation network has been found to coincide with a periodic variation in the composition at the Si/Si.sub.1-xGe.sub.x interface and is believed to result from the defect-medicated diffusion of Si atoms from the Si substrate through the Si.sub.1-xGe.sub.x layer to the above SiO.sub.2 layer. The epitaxial growth of GaAs on such ultra-thin substrates is demonstrated, presenting a promising approach for solving the long-standing challenge of local, monolithic integration of III-V optoelectronics on the Si platform.

The present invention discloses a solar-blind AlGaN ultraviolet (UV) photodetector and a preparation method thereof. The solar-blind AlGaN UV photodetector comprises an UV photodetector epitaxial wafer, including an undoped N-polar plane AlN buffer layer, a carbon-doped N-polar plane AlN layer, a carbon-doped N-polar plane composition-graded Al.sub.yGa.sub.1-yN layer, and an undoped N-polar plane Al.sub.xGa.sub.1-xN layer that are grown sequentially on a silicon substrate, and also comprises an insulating layer, an ohmic contact electrode, and a Schottky contact electrode arranged on the UV photodetector epitaxial wafer, as well as a SiN.sub.z passivation layer arranged on both sides of the UV photodetector epitaxial wafer, where x=0.5-0.8, y=0.75-0.95, and z=1.33-1.5. The present invention realizes the preparation of the high-performance solar-blind AlGaN UV photodetector, and improves the responsivity and detectivity of the AlGaN UV photodetector' in the UV solar-blind band.

A composition of matter comprising: a plurality of group III-V nanowires or nanopyramids epitaxially grown on a polycrystalline or single-crystalline graphene layer, said graphene layer being directly supported on a crystalline substrate such as a group III-V semiconductor, sapphire, SiC or diamond substrate, wherein the epitaxy, crystal orientation and facet orientations of said nanowires or nanopyramids are directed by the crystalline substrate.

An optoelectronic device is manufactured by an epitaxial growth, on each first layer of many first layers spaced apart from each other on a first support, wherein the first is made of a first semiconductor material, of a second layer made of a second semiconductor material. A further epitaxial growth is made on each second layer of a stack of semiconductor layers. Each stack includes a third layer made of a third semiconductor material in physical contact with the second layer. Each stack is then separated from the first layer by removing the second layer using an etching that is selective simultaneously over both the first and third semiconductor materials. Each stack is then transferred onto a second support. Each of the first and third semiconductor materials is one of a III-V compound or a II-VI compound.

A method of fabricating a four junction solar cell by identifying the composition and band gaps of the upper first, second and third subcells that maximizes the efficiency of the solar cell at a predetermined time after initial deployment by simulation; fabricating one or more four-junction test solar cells in accordance with the identified composition and band gaps of the upper first, second and third subcells; performing one or more optical or electrical tests on the fabricated one or more four-junction test solar cells; based on results of the tests, determining one or more properties of at least one of the upper first, second or third subcells to be modified in subsequent fabrication of four-junction solar cells, including the band gap, doping level and profile, and thickness of each of the subcell layers; and fabricating a further four-junction solar cell in accordance with the modified properties of at least one of the upper first, second or third subcells to optimize the efficiency of the solar cell at the predetermined time.