What are Nanowires
A lot of the micro-electronic technology still in use today is largely a result of breakthroughs made before the 1950’s. Moore ’s Law, the doubling of semiconductor technology every 18 months has pretty much described the growth of computing and microelectronic technology accurately through the last several decades. But we are now on the cusp of a technological revolution –a nanotechnological one. Nanotechnology’s exception to certain laws of physics in the macro world holds much promise for a completely new generation of microelectronics –their next generation. One such marvel of nanotechnology, though still in the laboratory stage, is the nanowire .
A “nanowire” is a lab-made suspended or deposited inorganic wire of the nano-scale, usually around 20-40 nanometers (one-billionth of a meter) in diameter that has unique electronic, magnetic, or optoelectronic characteristics. Though nanowires (very similar to nanotubes) can have very different shapes, they are often thin, needlelike threads. They have been successfully “knitted” into films and lattice-like graphs that may prove useful for electronic coatings or fabrics.
Nanowires usually range from semi-conductive to super-conductive, but at nanotechnology’s small scales, quantum effects dominate the electronic interactions, and the quantum-confined nature of these wires allows them to behave much differently than the macro-scale wires we are used to. They conduct and carry electrons differently, have odd magnetic characteristics, and even behave in scientifically unpredictable ways.
Of course, once these odd behaviors are harnessed -something that we are currently in the process of doing, the technological applications of these wires should be profound.
One common technique for creating nanowires is the Vapor-Liquid-Solid synthesis method. With this method, a laser-ablated or feed-gas material is exposed to a catalyst –usually a metal or nanoclusters. This method usually creates crystalline structure nanowires, a common use as a semi-conductive material.
Below are lists of probable applications for nanowires, properties, and the common materials they are made of or adhered to.
Applications
•Nano-scale electrical circuits made out of compounds that are capable of being formed into extremely small circuits (nanoelectronic circuits).
•High density data storage (magnetic heads and patterned storage media).
•Computing –semiconductors, superconductors, transistors, logic gates.
•Magneto-optical switches (useful in photonics, where light relays data).
•Nanoscale optoelectronics, field effect transistors, decoders, lasers, chemical and bio sensors, LEDs.
•Optical splitters (to split a signal in nanometer-scale photonic systems).
•Metallic interconnects of quantum devices and nanodevices, nanoprobes.
•Detection of the presence of altered genes (possibly associated with cancer) with nano sized sensing wires inside microfluidic channels.
Properties
•Erratic regulation of electron speeds.
•Limitations to the density of available phonon states.
•Spontaneous division into branching structures.
Types and materials; substrates, masks, dopings, catalysts, coatings, and deposits
•Metallic and magnetic
•Thermoelectric performance
•Semiconductor
•Multi-shell gold
•Bi, Ni, ZnO
•Tubular aluminum
•Silicon, silica
•Ultrathin rhodium
•Polymer
•Indium phosphide
•Phenyleneethynylene, oligophenyleneethynylene
•Nanoporous
•Nickel
•G-quartet biomolecular
•Multilayered
•Silicon wafers (as substrate)
•Calcium fluoride (as mask)
•Germanium
•Galium nitride
•Carbon
•Thin film
•Single-crystalline superlattice
•Semiconductor heterostructure
•Semimetallic bismuth
•Coaxial crystalline
•Zinc-oxide
•Pentagonal multi-shell Cu
•Teflon amorphous fluoropolymer thin film
