An optoelectronic device comprising: a first conductive layer, a second conductive layer, an active layer between the first conductive layer and the second conductive layer, wherein the active layer comprises a submicrometer size structure of hexagonal type crystals of an element or alloy of elements selected from the carbon group.

Techniques for enhancing the absorption of photons in semiconductors with the use of microstructures are described. The microstructures, such as pillars and/or holes, effectively increase the effective absorption length resulting in a greater absorption of the photons. Using microstructures for absorption enhancement for silicon photodiodes and silicon avalanche photodiodes can result in bandwidths in excess of 10 Gb/s at photons with wavelengths of 850 nm, and with quantum efficiencies of approximately 90% or more.

An ultraviolet detecting silicon carbide junction field effect transistor with a transistor gate junction positioned proximate to the outer surface to receive ultraviolet: light and flow an ultraviolet light induced photo current when reverse biased.

An ultraviolet detecting silicon carbide junction field effect transistor with a transistor gate junction positioned proximate to the outer surface to receive ultraviolet: light and flow an ultraviolet light induced photo current when reverse biased.

A photodetector includes a first semiconductor layer including germanium, a conductive layer that, in conjunction with the first semiconductor layer, forms a Schottky junction structure, and a tunneling barrier layer positioned between the first semiconductor layer and the conductive layer and configured to prevent dark current between the first semiconductor layer and the conductive layer.

An apparatus comprising a plurality of solar cells that each comprise a nanowire titanium oxide core having graphene disposed thereon. By one approach this plurality of solar cells can comprise, at least in part, a titanium foil having the plurality of solar cells disposed thereon wherein at least a majority of the solar cells are aligned substantially parallel to one another and substantially perpendicular to the titanium foil. Such a plurality of solar cells can be disposed between a source of light and another modality of solar energy conversion such that both the solar cells and the another modality of solar energy conversion generate electricity using a same source of light.

Various particular embodiments include a method for forming a photodetector, including: forming a structure including a barrier layer disposed between a layer of doped silicon (Si) and a layer of germanium (Ge), the barrier layer including a crystallization window; and annealing the structure to convert, via the crystallization window, the Ge to a first composition of silicon germanium (SiGe) and the doped Si to a second composition of SiGe.

A photovoltaic device and method include a doped germanium-containing substrate, an emitter contact coupled to the substrate on a first side and a back contact coupled to the substrate on a side opposite the first side. The emitter includes at least one doped layer of an opposite conductivity type as that of the substrate and the back contact includes at least one doped layer of the same conductivity type as that of the substrate. The at least one doped layer of the emitter contact or the at least one doped layer of the back contact is in direct contact with the substrate, and the at least one doped layer of the emitter contact or the back contact includes an n-type material having an electron affinity smaller than that of the substrate, or a p-type material having a hole affinity larger than that of the substrate.

Semiconductor devices, such as photonics devices, employ substantially curved-shaped Silicon-Germanium (SiGe) structures and are fabricated using zero-change CMOS fabrication process technologies. In one example, a closed-loop resonator waveguide-coupled photodetector includes a silicon resonator structure formed in a silicon substrate, interdigitated n-doped well-implant regions and p-doped well-implant regions forming multiple silicon p-n junctions around the silicon resonator structure, and a closed-loop SiGe photocarrier generation region formed in a pocket within the interdigitated n-doped and p-doped well implant regions. The closed-loop SiGe region is located so as to substantially overlap with an optical mode of radiation when present in the silicon resonator structure, and traverses the multiple silicon p-n junctions around the silicon resonator structure. Electric fields arising from the respective p-n silicon junctions significantly facilitate a flow of the generated photocarriers between electric contact regions of the photodetector.

An image sensor array including a carrier substrate; a first group of photodiodes coupled to the carrier substrate, where the first group of photodiodes include a first photodiode, and where the first photodiode includes a semiconductor layer configured to absorb photons at visible wavelengths and to generate photo-carriers from the absorbed photons; and a second group of photodiodes coupled to the carrier substrate, where the second group of photodiodes include a second photodiode, and where the second photodiode includes a germanium-silicon region fabricated on the semiconductor layer, the germanium-silicon region configured to absorb photons at infrared or near-infrared wavelengths and to generate photo-carriers from the absorbed photons.