Nanotechnology refers broadly to a field of
applied science and technology whose unifying theme is the control of matter on the atomic and
molecular scale, normally 1 to 100 nanometers, and the fabrication of devices within that size range. It is a highly
multidisciplinary field, drawing from fields such as
applied physics,
materials science,
colloidal science,
device physics,
supramolecular chemistry, and even
mechanical and
electrical engineering. Much speculation exists as to what new science and technology may result from these lines of research. Nanotechnology can be seen as an extension of existing sciences into the nanoscale, or as a recasting of existing sciences using a newer, more modern term. Two main approaches are used in nanotechnology. In the "bottom-up" approach, materials and devices are built from
molecular components which
assemble themselves chemically by principles of
molecular recognition. In the "top-down" approach, nano-objects are constructed from larger entities without atomic-level control. The impetus for nanotechnology comes from a renewed interest in colloidal science, coupled with a new generation of analytical tools such as the
atomic force microscope (AFM), and the
scanning tunneling microscope (STM). Combined with refined processes such as
electron beam lithography and
molecular beam epitaxy, these instruments allow the deliberate manipulation of nanostructures, and led to the observation of novel phenomena. Examples of nanotechnology in modern use are the manufacture of polymers based on molecular structure, and the design of
computer chip layouts based on surface science. Despite the great promise of numerous nanotechnologies such as
quantum dots and
nanotubes, real commercial applications have mainly used the advantages of colloidal nanoparticles in bulk form, such as
suntan lotion,
cosmetics,
protective coatings, and stain resistant clothing.
See more at Wikipedia.org...
/nan'-oh-tek-no"l*-jee/ Any fabrication technology in which objects are designed and built by the specification and placement of individual atoms or molecules or where at least one dimension is on a scale of
nanometers.
The first unequivocal nanofabrication experiments took place in 1990, for example with the deposition of individual xenon atoms on a nickel substrate to spell the logo of a certain very large computer company.
Nanotechnology has been a hot topic in the hacker subculture ever since the term was coined by K. Eric Drexler in his book "Engines of Creation", where he predicted that nanotechnology could give rise to replicating assemblers, permitting an exponential growth of productivity and personal wealth.
See also
nanobot.
http://www.lucifer.com/~sean/Nano.html.
(2003-05-02)
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