A semiconductor device has a layered structure. The semiconductor device includes a metallic layer of thickness 1-100 nm, with a thickness optimized to absorb light in a wavelength range of operation. The device further includes an adjacent semiconductor layer additionally adjacent to an ohmic electrical contact, wherein the interface between the metallic layer and the semiconductor layer is electrically rectifying and energy selective. The device further includes a reflective back surface positioned opposite to the semiconductor layer relative to incident light providing broadband reflection in the wavelength range of operation. The semiconductor layer includes a quantum well adjacent to the metallic layer, wherein the energy selectivity is provided by the quantum well allowing charge carrier tunneling from the metallic layer. The device further may include an additional anti-reflection dielectric layer deposited on the metallic layer that is configured to minimize reflection of light in the wavelength range of operation.

A gas sensor containing counter electrodes and a semiconductor nanowire 4 disposed between the counter electrodes 2, 3, wherein the semiconductor nanowire 4 is in a state where light can be irradiated, which sensor measures changes in the electric current associated with adsorption of a gas to the semiconductor nanowire 4, wherein the electric current is generated by irradiation of light on the semiconductor nanowire with a voltage applied to the counter electrodes 2, 3.

Described herein are microfluidic devices and methods of detecting an analyte in a sample that includes flowing the sample though a microfluidic device, wherein the presence of the analyte is detected directly from the microfluidic device without the use of an external detector at an outlet of the microfluidic device. In a more specific aspect, detection is performed by incorporating functional nanopillars, such as detector nanopillars and/or light source nanopillars, into a microchannel of a microfluidic device.

The present invention relates to a solar cell having nanostructures on both surfaces of a transparent substrate, and to a method for manufacturing same. The nano-structures, which face each other with respect to the substrate and which transport electrons, are formed using zinc-oxide nanowires. Also, a hole-transport layer using CIS nanoparticles is formed in order to absorb light having a short wavelength and to transport generated holes. A hole-transport layer including CIGS nanoparticles for absorbing light having a relatively long wavelength is formed on the side facing the hole-transport layer including the CIS nanoparticles.

An optoelectronic device configured for improved light extraction through a region of the device other than the substrate is described. A group III nitride semiconductor layer of a first polarity is located on the substrate and an active region can be located on the group III nitride semiconductor layer. A group III nitride semiconductor layer of a second polarity, different from the first polarity, can located adjacent to the active region. A first contact can directly contact the group III nitride semiconductor layer of the first polarity and a second contact can directly contact the group III nitride semiconductor layer of the second polarity. Each of the first and second contacts can include a plurality of openings extending entirely there through and the first and second contacts can form a photonic crystal structure. Some or all of the group III nitride semiconductor layers can be located in nanostructures.

A heterostructure for use in an electronic or optoelectronic device is provided. The heterostructure includes one or more semiconductor layers containing columnar nanostructures (e.g., nanowires). The nanowire semiconductor layer can include sub-layers of varying composition, at least one of which is an active layer that can include quantum wells and barriers. A heterostructure can include n-type and p-type semiconductor contact layers adjacent to the nanowire semiconductor layer containing the active layer.

Example photoconductive devices and example methods for using photoconductive devices are described. An example method may include providing a photoconductive device having a metal-semiconductor-metal structure. The method may also include controlling, based on a first input state, illumination of the photoconductive device by a first optical beam during a time period, and controlling, based on a second input state, illumination of the photoconductive device by a second optical beam during the time period. Further, the method may include detecting an amount of current produced by the photoconductive device during the time period, and based on the detected amount of current, providing an output indicative of the first input state and the second input state. The example devices can be used individually as discrete components or in integrated circuits for memory or logic applications.

A device including at least one photovoltaic cell and at least one nanowire configured to electrically stimulate a biological material in response to radiation.

Methods are provided for controlling the shape of antimony selenide (Sb.sub.2Se.sub.3) synthesized nanostructures. The method dissolves an antimony (III) salt in a first amount of carboxylic acid, forming an antimony precursor. In one aspect, antimony (III) chloride is dissolved in oleic acid. Separately, selenourea is dissolved in oleylamine, forming a selenium precursor. The antimony precursor is combined with the selenium precursor to form a first solution and cause a reaction. The reaction is quenched with a solvent having a low boiling point. In response to quenching the reaction in the first solution, antimony selenide nanorods are formed, having a length in the range of 150-200 nanometers (nm) and a diameter in the range of 20 to 30 nm. Related methods can be used to create, shorter nanorods, nanocrystals, and hollow nanospheres.

One embodiment of the present invention relates to a method for manufacturing solar cells having a nano-micro composite structure on a silicon substrate and solar cells manufactured thereby. The technical problem to be solved is to provide a method for manufacturing solar cells and solar cells manufactured thereby, the method being capable of forming micro wires in various sizes according to the lithographic design of a photoresist and forming nano wires, which have various sizes and aspect ratios, by adjusting the concentration of a wet etching solution and immersion time. To this end, the present invention provides a method for manufacturing solar cells and solar cells manufactured thereby, the method comprising the steps of: preparing a first conductive semiconductor substrate having a first surface and a second surface; patterning a photoresist on the second surface of the first conductive semiconductor substrate such that the plane form of the photoresist becomes a form in which multiple horizontal lines and multiple vertical lines intersect each other; electrolessly etching the semiconductor substrate so as to form a micro wire having a width of 1-3 m and a height of 3-5 m in a region corresponding to the photoresist and to form multiple nano wires having a width of 1-100 nm and a height of 1-3 m in a region not corresponding to the photoresist; doping the micro wire and nano wires with a second conductive impurity by using POCl.sub.3; forming a first electrode on the first surface of the semiconductor substrate; and forming a second electrode on the micro wire, wherein the efficiency of the solar cells is 10-13%, the efficiency being the ratio of output to incident light energy per unit area.