A method of manufacturing a semiconductor device includes providing a substrate structure. The substrate structure includes a conductive layer and a plurality of nanopillars spaced apart from each other overlying the conductive layer. Each nanopillar includes a first semiconductor layer and a second semiconductor layer on the first semiconductor layer. The first semiconductor layer and the second semiconductor layer have different conductivity types. The method also includes forming a graphene layer overlying the plurality of nanopillars. The graphene layer is connected to each of the plurality of nanopillars.

An apparatus comprising a substrate, one or more nanowire pillars, each having a base portion and a tip portion, a first electrode connected to the tip portions of the one or more nanowire pillars, an internal hollow cavity positioned between the substrate and the first electrode, such that at least a portion of each of the one or more nanowire pillars extend through the internal hollow cavity, and a second electrode proximate the first side of the substrate. High-performance broadband photodetectors and other optoelectronics for converting light to electricity with enhanced absorption and carrier collection.

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.

Devices for generating electrical energy along with methods of fabrication and methods of use are disclosed. An example device can comprise one or more layers of a transition metal dichalcogenide material. An example device can comprise a mechano-electric generator. Another example device can comprise a thermoelectric generator.

Photovoltaic devices, and methods of fabricating photovoltaic devices. The photovoltaic devices may include a first electrode, at least one quantum dot layer, at least one semiconductor layer, and a second electrode. The first electrode may include a layer including Cr and one or more silver contacts.

A light emitting diode device comprising: a plurality of nanowires or nanopyramids grown on a graphitic substrate, said nanowires or nanopyramids having a p-n or p-i-n junction, a first electrode in electrical contact with said graphitic substrate; a light reflective layer in contact with the top of at least a portion of said nanowires or nanopyramids, said light reflective layer optionally acting as a second electrode; optionally a second electrode in electrical contact with the top of at least a portion of said nanowires or nanopyramids, said second electrode being essential where said light reflective layer does not act as an electrode; wherein said nanowires or nanopyramids comprise at least one group III-V compound semiconductor; and wherein in use light is emitted from said device in a direction substantially opposite to said light reflective layer.

Provided is a sensor with nanowires in an aligned array. In one example, the heaviest doped region is not in the nanowire array, but in the bulk silicon substrate and the sensor is functionalized to be have modified electrical properties when proteins are present.

A quantum wire device includes a barrier formed by an insulator or a wide bandgap semiconductor, and metal quantum wires comprising a metal material and embedded in the barrier. Potential wells are formed for electrons in the metal quantum wires by the insulator or the wide bandgap semiconductor. The work function of the metal quantum wires is reduced by quantum confinement compared to a bulk form of the metal material. The metal quantum wires are electrically connected. The metal quantum wires include an exposed active area for electron emission or electron collection.

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 intermediate series-connecting layer, a laminated photovoltaic device and a fabricating method are provided. The intermediate series-connecting layer is light-transmittable; the intermediate series-connecting layer includes a longitudinal conducting layer; and the longitudinal conducting layer is formed by nano-sized conducting columns that longitudinally grow; or the longitudinal conducting layer includes nano-sized conducting units that are separately distributed, and insulating and separating bodies located between neighboring the nano-sized conducting units, and the insulating and separating bodies transversely insulate the nano-sized conducting units. A large quantity of grain boundaries or interfaces are located between the nano-sized conducting columns, and have a poor transverse conducting performance, the longitudinal conducting layer has a poor transverse conducting capacity, the charge carriers are mainly longitudinally transmitted, and there is substantially no transverse current. Alternatively, the nano-sized conducting units are insulated by the insulating grids in the transverse direction.