The present invention provides nanometer-sized diameter silica fibers that exhibit high diameter uniformity and surface smoothness. The silica fibers can have diameters in a range of a about 20 nm to about 1000 nm. An exemplary method according to one embodiment of the invention for generating such fibers utilizes a two-step process in which in an initial step a micrometer sized diameter silica preform fiber is generated, and in a second step, the silica preform is drawn while coupled to a support element to form a nanometer sized diameter silica fiber. The portion of the support element to which the preform is coupled is maintained at a temperature suitable for drawing the nansized fiber, and is preferably controlled to exhibit a temporally stable temperature profile.

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Subwavelength-diameter silica wires for low-loss optical waveguiding

This invention provides novel nanofiber enhanced surface area substrates and structures comprising such substrates for use in various medical devices, as well as methods and uses for such substrates and medical devices. In one particular embodiment, methods for enhancing cellular functions on a surface of a medical device implant are disclosed which generally comprise providing a medical device implant comprising a plurality of nanofibers (e.g., nanowires) thereon and exposing the medical device implant to cells such as osteoblasts.

Medical device applications of nanostructured surfaces

One-dimensional nanostructures having uniform diameters of less than approximately 200 nm. These inventive nanostructures, which we refer to as “nanowires”, include single-crystalline homostructures as well as heterostructures of at least two single-crystalline materials having different chemical compositions. Because single-crystalline materials are used to form the heterostructure, the resultant heterostructure will be single-crystalline as well. The nanowire heterostructures are generally based on a semiconducting wire wherein the doping and composition are controlled in either the longitudinal or radial directions, or in both directions, to yield a wire that comprises different materials. Examples of resulting nanowire heterostructures include a longitudinal heterostructure nanowire (LOHN) and a coaxial heterostructure nanowire (COHN).

Methods of fabricating nanostructures and nanowires and devices fabricated therefrom

The present invention relates generally to sub-microelectronic circuitry, and more particularly to nanometer-scale articles, including nanoscale wires which can be selectively doped at various locations and at various levels. In some cases, the articles may be single crystals. The nanoscale wires can be doped, for example, differentially along their length, or radially, and either in terms of identity of dopant, concentration of dopant, or both. This may be used to provide both n-type and p-type conductivity in a single item, or in different items in close proximity to each other, such as in a crossbar array. The fabrication and growth of such articles is described, and the arrangement of such articles to fabricate electronic, optoelectronic, or spintronic devices and components. For example, semiconductor materials can be doped to form n-type and p-type semiconductor regions for making a variety of devices such as field effect transistors, bipolar transistors, complementary inverters, tunnel diodes, light emitting diodes, sensors, and the like.

Nanoscale wires and related devices

The present invention is directed to compositions (“Nanomaterial Polymer Compositions”) comprising a silicone polymer and a nanomaterial, including but not limited to, a single or multi-walled nanotube, a nanowire, a nanodot, a quantum dot, a nanorod, a nanocrystal, a nanotetrapod, a nanotripod, a nanobipod, a nanoparticle, a nanosaw, a nanospring, a nanoribbon, a branched nanomaterial, or any combination thereof. The Nanomaterial Polymer Compositions are useful for optical and sensing devices including but not limited to noise suppression, passive Q-switching, mode-locking, waveform shaping, optical switching, optical signal regeneration, phase conjugation or filter devices, dispersion compensation, wavelength conversion, a soliton stabilization, microcavity applications, interferometers; optical, magneto-optical or electro-optical modulation; and biochemical sensors and photodetectors. The Nanomaterial Polymer Compositions are also useful in soft lithography processes.

Nanomaterial polymer compositions and uses thereof

A bulk-doped semiconductor that is at least one of the following: a single crystal, an elongated and bulk-doped semiconductor that, at any point along its longitudinal axis, has a largest cross-sectional dimension less than 500 nanometers, and a free-standing and bulk-doped semiconductor with at least one portion having a smallest width of less than 500 nanometers. Such a semiconductor may comprise an interior core comprising a first semiconductor; and an exterior shell comprising a different material than the first semiconductor. Such a semiconductor may be elongated and may have, at any point along a longitudinal section of such a semiconductor, a ratio of the length of the section to a longest width is greater than 4:1, or greater than 10:1, or greater than 100:1, or even greater than 1000:1. At least one portion of such a semiconductor may a smallest width of less than 200 nanometers, or less than 150 nanometers, or less than 100 nanometers, or less than 80 nanometers, or less than 70 nanometers, or less than 60 nanometers, or less than 40 nanometers, or less than 20 nanometers, or less than 10 nanometers, or even less than 5 nanometers. Such a semiconductor may be a single crystal and may be free-standing. Such a semiconductor may be either lightly n-doped, heavily n-doped, lightly p-doped or heavily p-doped. Such a semiconductor may be doped during growth. Such a semiconductor may be part of a device, which may include any of a variety of devices and combinations thereof, and a variety of assembling techniques may be used to fabricate devices from such a semiconductor. Two or more of such a semiconductors, including an array of such semiconductors, may be combined to form devices, for example, to form a crossed p-n junction of a device. Such devices at certain sizes may exhibit quantum confinement and other quantum phenomena, and the wavelength of light emitted from one or more of such semiconductors may be controlled by selecting a width of such semiconductors. Such semiconductors and device made therefrom may be used for a variety of applications.

Doped elongated semiconductors, growing such semiconductors, devices including such semiconductors, and fabricating such devices

A method for depositing one or more semiconductor nanowires on a substrate, the method comprising providing a substrate and depositing the one or more semiconductor nanowires on the surface of the substrate.

Electrical device comprising doped semiconductor nanowires and method for its production

A method comprises providing a population of catalyst particles and growing a population of semiconductor nanowires catalytically from the population of catalyst particles. The nanowires of the population have a variation in diameter of less than about 20%, and the nanowires of the population have a smallest width less than 500 nanometers. Preferably the nanowires of the population have a variation in diameter of less than about 10%.

Yung-Sheng Huang

Papers

Doped elongated semiconductors, growing such semiconductors, devices including such semiconductors, and fabricating such devices

Electrical device comprising doped semiconductor nanowires and method for its production

Method for growing nanowires

Method for depositing a semiconductor nanowire

Verfahren zur Abscheidung eines halbleitenden Nanodrahtes