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Nanotechnology will soon become a household
word. It is a leading-edge technology that will revolutionize
many sectors of manufacturing over the long-term. The situation
is somewhat analogous to that of biotechnology and genetic
engineering—a field that, 15 or 20 years ago, few people
could define. Even fewer could envision how the biotechnology
industry would fundamentally change the development of drugs
and diagnostics.
Nanotechnology is generally defined as the science of designing,
building or utilizing unique structures that are smaller than
100 nanometers in size (a nanometer is one billionth of a
meter). This involves microscopic structures that are no larger
than the width of some cell membranes. In particular, nanotech
may involve the manipulation of materials on the atomic level
so that they take on new characteristics, such as increased
strength.
MEMS refers to the very exciting field of the miniaturization
of electronics. Specifically, we define MEMS as “Micro
Electro Mechanical Systems,” micron-scale structures
that transduce signals between electronic and mechanical forms.
Nanotechnology will interface with such technologies as electronics,
biotechnology, chemistry, robotics and aerospace. The result
will be new ways to solve problems and create products, based
on the use of micro components.
Over the next few years, the fastest-growing commercialized
uses of nanotechnology will most likely be in coatings (including
advanced paints used in demanding environments), specialty
chemicals (with many different applications) and textiles
(for example, new stain-free pants were introduced by Eddie
Bauer and Lee Jeans in 2003, based on micro textile technology).
Much wider uses of nanotechnology will eventually be commercialized.
However, practical realizations of most potential applications
of nanotechnology are still many years away.
An early use of MEMS technology that currently affects consumers
is the micro switches that are used in passenger-side airbags.
These MEMS switches must be accurate enough to determine when,
and at what level of strength, a collision occurs, and then
set off the inflation of the air bag quickly enough to protect
passengers before the collision’s impact reaches them.
What is Nanotechnology?
One of the biggest problems in investigating the nanotechnology
industry is separating overly optimistic claims and notions
from practical capabilities and feasible developments. The
purpose of this chapter is to give the reader a brief overview
of nanotechnology, what it means, what has been done, including
major areas of application, and what might be expected in
the future. Because nanotechnology is such a new field, it
is also one of the least understood. Hopefully this chapter
will give enough of a background to provide the reader with
an educated perspective on this fascinating and rapidly advancing
science, as well as the ability to discern the difference
between real nanotechnology and science fiction.
Nanotechnology is actually a catch-all term for anything on
the scale of nanometers (nm). A nanometer is one billionth
of a meter, and nanotechnology is generally anything that
is done or built on a scale between 0.1 and 100 nm in size.
To give some perspective on how small this really is, consider
that a line of 10 hydrogen atoms is one nanometer across;
red blood cells are thousands of nanometers across; and a
human hair is about 100,000 nanometers across. Adjectives
fail to describe how small a nanometer is. (In contrast, MEMS
are measured on the micrometer scale. A micrometer is one
millionth of a meter, or a thousand times larger than a nanometer.)
The importance of being able to manipulate things on the nanoscale
is not just that they are very small, or that they are the
smallest devices known up to this point in time. Because this
is the scale of atoms and molecules, it is as small as materials
may ever get. This is near the most basic level of matter
itself. What this means is that we are not only making smaller
materials, we are actually changing the nature of materials
themselves on the molecular or atomic level, in order to make
them stronger, lighter or more flexible. We can make structures
out of individual atoms, decide whether we want 10, 50 or
100 atoms and how we want them to line up. This is the ultimate
level of precision. By mastering nanotechnology, we can make
or manipulate materials to suit our needs, rather than using
what materials are available in their given form.
Another important point about materials on the nanoscale is
that they behave differently than macroscale materials. Forces
such as gravity and friction have different properties and
therefore different effects at this scale. The most prominent
forces affecting nanomaterials are atomic forces, chemical
bonds and quantum mechanics—in many cases our ability
to manipulate these forces is in the very early stages. To
grasp this concept, consider the fact that you could make
a fully functioning, tiny automobile that was only a millimeter
long; but you could not make the same car in nanoscale, say
a couple of nanometers long, because you would then be attempting
to construct engine parts out of individual atoms, and vital
details such as combustion and moving gears simply wouldn’t
be possible with current or near-term technologies.
Nanotechnology is new in more ways than one. We have to adopt
an entirely new set of rules, and then design structures and
machines around those rules. Many of the things we have made
before cannot be constructed in nanoscale, but nanotechnology
will enable us to construct things that were not previously
possible.
Nanotechnology is still in its infancy, but it is rapidly
growing into adolescence. The initial groundwork of building
microscopes that can probe into such a minute scale, as well
as devices that can perform basic molecular manipulation,
has been laid. We are now at the stage of investigating basic
structures that have promising properties, such as nanotubes
and nanowires, and we have set before us the tasks of finding
useful applications and learning how to produce and commercialize
them on an industrial scale. This exploration has begun with
basic applications such as advanced coatings and powders for
ceramics, textiles, gels and laminates. More advanced applications
such as nanoscale computing devices are in the works and will
come later. It is only a matter of time.
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