Small size - large impact - Nanowerk

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Myth 1: Nanotechnology is a distinct,
previously unknown discipline
Nanotechnology actually embraces advancements over
a wide range of scientific and technical disciplines –
physics, chemistry, biology, materials science, mechanics,
and electronics, to name just a few. Commonly
designated as the science and technology in which at least
one dimension is controlled to less than 100 nanometers,
it may, in fact, be best to think of nanotechnology as
an engineering discipline: its aim is to design and build
structures and devices on this very small-length scale
using tools from whatever field is appropriate.
Although the word is relatively new, nanotechnology
has been around for some time. Chemists and biologists,
for example, have long been able to design and create
molecules with specific atomic structures. Typically,
this could be done only in batches with relatively large
collections of molecules. Over the past 20 years or
so, scientists and engineers have increasingly extended
the ability to view and manipulate ever smaller bits
of matter – in some cases individual atoms. While
nanoparticle additives to paints and clothing,
molecular circuit elements and designer drugs can
all be considered nanotechnologies, these applications
have little in common beyond their use of materials
designed and structured at the nanometer scale.
In the IT industry, semiconductor manufacturers are
now producing chips with minimum lithographic
dimensions which measure a mere 90 nanometers or
less and feature millions of transistors. The experimental
silicon transistors in our laboratories are smaller yet. A
mere 6 nanometers for the critical gate length is the current
frontier – the kind of innovation that IT relies upon
to build devices that are ever smaller, faster and cheaper.
Myth 2: The primary goal of nanotechnololgy
is to create self-assembling nanobots
Researchers today are hardly creating the self-replicating
nanobots of science fiction, Instead, they are working
on the so-called directed self-assembly of nanoscale
materials and devices, aiming to exploit the natural
tendency of atoms and molecules to orient themselves,
react, and bind with each other in predictable ways
under the right conditions.
Self-assembly is nothing other than exploitation of
the laws of thermodynamics and kinetics which drive
all natural phenomena. Consider a snowflake, which
is created when water molecules floating in a cloud
coalesce around a grain of dust and crystallize to create
a new structure. While a snowflake may have a complex
structure, it is far from alive and does not self-replicate.
Nevertheless, when conditions are right, nature makes
trillions of them quickly and cheaply.
By taking advantage of such natural forces, scientists try
to discover the conditions to form technologically useful
new materials and devices. They are currently exploring
the directed assembly of transistors and circuits based
on carbon nanotubes, semiconductor nanowires and
molecular building blocks. Further, they are developing
self-assembled materials for data storage and memory.
In the future, processes of directed self-assembly are
likely to be used increasingly in combination with
today’s photolithography to reduce the reliance on this
ever more expensive method for semiconductor
manufacturing. In this sense, the often-cited contrast
between top-down (photolithography) versus bottom-up
(self-assembly) approaches to device fabrication is a false
dichotomy. A hybrid of the two already is – and will
continue to be – employed.
Myth 3: Nanotechnology will
replace microelectronics
Microelectronics is a nanotechnology, as are hard-disk
drives whose giant-magnetoresistive read heads and
magnetic media rely on layers of materials only a few
atoms thick to give computers ever more storage capacity.
Rather than suddenly replacing today’s methods for
chip manufacture, it is more likely that individual
nanostructures and nanodevices and new manufacturing
processes will increasingly be integrated into the
mainstream. Transistors made out of the new materials
being considered, such as carbon nanotubes and
semiconductor nanowires, might not be much smaller
than that experimental 6-nanometer silicon transistor
mentioned above. Silicon probably has a promising
future as a nanomaterial.
That being said, there are numerous, innovative
alternatives being explored to augment the capabilities
of integrated circuits. Particularly interesting is the
prospect of using physical phenomena other than simple
manipulation of electronic charge in future computing
devices, such as the spin of electrons (so-called
spintronics) or even nanoscale mechanics.
Challenges and opportunities for the future
of the IT industry
While nanotechnology is already contributing to
the ongoing progress and extension of IT technology,
the future is not without its challenges. The scaling
of semiconductor technology known as Moore’s Law
may continue for another decade or so, allowing us to
eventually fabricate transistors with critical dimensions
approaching 10 nanometer. After that, a transition
in technological hardware and, a long lead-time for
developing new technologies can be expected. As such,
the IT industry is working now on the successor to
conventional CMOS semiconductor technology.