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					NANOTECHNOLOGY




(APPLICATIONS OF NANOTECH)


PRESENTED BY:
ASHWINI PULLABHATLA
AND
R. JAYASREE REDDY
GNITS
HYDERABAD
INTRODUCTION:

One of the most exciting and fastest growing areas in science and engineering today is
nanotechnology. The subject arises from the convergence of physics, chemistry, biology,
materials science and electronics to create new functional systems of nanoscale
dimensions of the order of a billionth of a meter! In recognition of the enormous range of
potential applications evolving from Nanotechnology, both the public and private sectors
worldwide are making huge investments in this field.
   Manufactured products are made from atoms. The properties of these products
depend on how these atoms are arranged. If we rearrange the atoms in coal we can make
diamond .If we rearrange the atoms in sand (and add a few other trace elements) we can
make computer chips. If we rearrange the atoms in dirt, water and air we can make
potatoes.




     Today’s manufacturing methods are very crude at the molecular level. Casting, grinding,
milling and even lithography move atoms in great thundering statistical herds. It’s like trying to
make things out of LEGO blocks with boxing gloves on your hands. yes, you can push the
LEGO blocks into great heaps and pile them up, but you can’t really snap them together the way
you’d like.
     In the future, nanotechnology will let us take off the boxing gloves. We’ll be able to snap
together the fundamental building blocks of nature easily, inexpensively and in most of the ways
permitted by the laws of physics. This will be essential if we are to continue the revolution in
computer hardware beyond about the next decade, and will also let us fabricate an entire new
generation of products that are cleaner, stronger, lighter and more precise.
     A technology based on the ability to build structures to complex, atomic specifications by
means of mechanosynthesis; this can be termed molecular nanotechnology. Nanotechnology
is the science of creating highly miniaturized machines that work on the molecular level.
     Nanotechnology, an emerging frontier-a realm in which machines operates at scales of
billionths of a meter. It is actually a multitude of rapidly emerging technologies, based upon the
scaling down of existing technologies to the next level of precision and miniaturization. The
original vision for nanotechnology is sometimes termed ‘molecular technology’or’molecular
manufacturing-based nanotechnology’.
     Nanotechnology is a hybrid science combining engineering, chemistry and to a certain extent
biology. Atoms and molecules stick together because they have complimentary shapes that lock
together or charges that attract. Just like magnets, a positively charged atom will stick to a
negatively charged atom. As millions of these atoms are pieced together by nanomachines, a
specific product will begin to take shape. The goal of nanotechnology is to manipulate atoms
individually and place them in a pattern to produce a desired structure.
    The future of nanotechnology at times becomes easier to predict. Computers will compute
faster, materials will become stronger and medicine will cure more diseases. The technology that
works at the nanometer scale of the molecules and atoms will be a large part of this future,
enabling great improvements in all fields of human presence. In the future decades, it could
make a super computer so small that it could barely be seen in a light microscope. Also
nanotechnology does propose to use self-replication, it does not propose to copy living systems.

    It’s worth pointing out that the word nanotechnology has become very popular and is used to
describe many types of research where the characteristics dimensions are less than about
1,000nm.For ex, continued improvements in lithography have resulted in line widths that are less
than 1micron:This work is often called nanotechnology.sub-micron lithography is clearly very
valuable but it is equally clear that conventional lithography will not let us build semiconductor
Devices in which individual dopant atoms are located at specific lattice sites. If we are
continuing these trends we will have to develop a new manufacturing technology, which will let
us inexpensively build computer systems with mole quantities of logic elements that are
molecular in both size and precision and are interconnected in complex and highly idiosyncratic
patterns. Nanotechnology will let us do this.
    When it’s unclear from the context whether we’re using the specific definition of
nanotechnology or the broader and more inclusive definition, we’ll use the terms “molecular
nanotechnology” or “molecular manufacturing”.
    Nanotechnology should let us:
    a) Get essentially every atom in the right place.
    b) Make almost any structure consistent with the laws of physics that we can specify in
molecular detail.
    c) Have manufacturing costs not greatly exceeding the cost of the required raw materials and
energy.
    There are two more concepts commonly associated with nanotechnology:
a) Positional assembly (to get the right molecular parts in the right places).
b) Massive Parallelism (to keep the cost down).
    The need for Positional assembly implies an interest in molecular robotics. E.g.) Robotic
devices that are molecular both in their size and precision. These molecular scale positional
devices are likely to resemble very small versions of their every day macroscopic counterparts.
    Positional assembly is frequently used in normal macroscopic manufacturing today and
provides tremendous advantages today.
    Nanotechnology could help revolutionize the industry, producing advances such as solar
power cells made of plastics to environmentally friendly batteries that detoxify themselves,
experts told United Press International. Thus Nanotechnology helps in improving the energy
options. Because nanomaterials have far more surface area for chemical reactions of storage,
they can become super catalysts. Electrical and thermal properties and strength of materials also
can improve dramatically. Simply put, nanotechnology is the creation of functional materials,
devices and systems through control of matter on the nanometer scale, and the exploitation of
novel properties and phenomena developed at that scale.
Nanochips:
As scientists and engineers continue to push back the limits of chip making technology,
they have quietly entered into the nanometer realm.
       For most people, the notion of harnessing nanotechnology for electronic circuitry
Suggests something wildly futuristic. In fact, if you have used a personal computer made
in the past few years, semiconductor built with nanometer_scale features most likely
processed your work.
             The recent strides are certainly impressive, but, you might ask, is
semiconductor manufacture really nanotechnology? Indeed it is. After all, the most
widely accepted definition of that word applies to something with dimensions smaller
than 100 nanometers, and the first transistor gate under this mark went into production in
2000.Integrated circuits coming to market now have gates that are a scant 50 nanometer
wide. That’s 50 billionths of a meter, about a thousandth the width of a human hair.
             Having such minuscule components conveniently allows one to stuff a lot
into a compact package, but saving space per se is not the impetus behind the push for
extreme miniaturization. The reason to make things small is that it lowers the unit cost for
each transistor. As a bonus, this overall miniaturization shrinks the size of the gates,
which are the parts of the transistors that switch between blocking electric current and
allowing it to pass. The more narrow the gates, the faster the transistors can turn on and
off, thereby raising the speed limits for the circuits using them. So as microprocessor gain
more transistors, they also gain more speed.
             The desire for boosting the number of transistors on a chip and for running it
faster explains why the semiconductor industry, just as it crossed into the new
millennium, shifted from manufacturing microchips to making nanochips. How it quietly
passed this milestone, and how it continues to advance, is an amazing story of people
overcoming some of the greatest engineering challenges of our time- challenges every bit
as formidable as those encountered in building the first atomic bomb or sending a person
to the moon.

STRAINING TO ACCELERATE:
The best way to get a flavor for the technical innovations that helped to usher in the
current era of nanochips is to survey improvements that have been made in each of the
stages required to manufacture a modern semiconductor. How in the world was this
marvel of engineering constructed? Let us survey the steps.
1.steam oxidizes the surface
2. Photoresist coats oxidized wafer
3. Lithography transfers desired pattern from mask to wafer
4. Chemicals and baking harden unexposed photoresist. Other parts of photoresist are
removed
5. Chemical etching selectivity strips off the oxide where no photoresist protects it. The
rest of the photoresist is removed
6. Ions shower etched areas, forming source and drain junctions
7. Metal contacts are added using lithography during later stages of fabrication.
NANOSENSORS:

Artificial sensors that are truly nanoscopic do not yet exist, as far as we know. Devices
that exploit the change in conductivity of nanotubes when they are exposed to specific
substances are perphas the closest to true nanosensors. Sensitivity to different chemical
species can be achieved by suitably functionalizing (i.e., attaching chemical groups to)
the sensing elements. Although the tubes and wires used in these sensors are several
microns long, it should be possible to make them shorter and still keep their sensing
capabilities. Chemical sensors based on microscopic cantilevers are being investigated by
several research groups, and often called nanosensors, but they are really microscale
devices. These sensors use two primary mechanisms:

   1. They detect the deflection of a cantilever caused by surface stresses that arise
      when a chemical species binds to one of the two opposing sides of the cantilever;
      or
   2. They measure the shift in the resonance frequency of a vibrating cantilever when
      its mass increases because of the deposition of the molecules being detected.




Using technology to prepare for future tsunamis. A possible scenario

Employing future technologies to prepare for tsunamis is timely for us all. The world will
continue to be at risk of tsunamis in the future. One scenario on how the Eastern United
States is at risk, for example, is a potential eruption of the La Palma volcano on the
Canary Islands off the coast of Africa. A half-trillion ton of volcanic rock could
potentially slip into the ocean and, in a worse case scenario, send a "mega-tsunami"
across the Atlantic Ocean.
This post is intended to promote hope in a future where we just might be prepared for
such disasters. There are various disaster scenarios and how molecular technologies can
give us hope in a future brighter than what we've experienced in 2004.



 Our Molecular Future: How Nanotechnology, Robotics, Genetics and Artificial
Intelligence Will Transform Our World,(a theoretical tsunami barrier manufactured
from carbon nanotubes)
Thousands of nanosensors implanted deep in the great calderas detect a huge magma
buildup thousands of feet below. Weeks pass. The volcano erupts. High-risk communities
have already moved thanks to disassembly and reassembly capabilities that arrived with
the deployment of nanotechnology. Tsunami warnings were raised along all coastlines.
Millions of vehicles were airborne in half an hour. Millions more potential victims made
it to the carbon-reinforced transport tunnels that permeate cities and double as evacuation
corridors.
As the tsunami approaches the coastline, graphite nanotube-reinforced curtains lower
themselves from a string of floating barriers that line the coast. As the curtains unravel
toward the sea floor, they position themselves to form a slope: an artificial shoreline. At
an electronic command, their molecular structure transforms from flexible to rigid. Still, a
series of weakened pulses pass through, submerging coastal cities up to the fifth-story
level.
Buildings are impregnated with carbon nanotubes thirty or more times stronger than steel,
rendering them virtually indestructible against wave action. Doors and windows are
hermetically sealed, turning buildings into submarines for the duration. External power
lines don't exist, having been replaced by transparent solar coatings on every building and
street.
Twenty-four hours pass and the flood subsides. Things are still ugly. Yet before residents
have returned to check the damage, an army of biological nanites--nano-scale
mechanical-biological mites--emerges to start consuming the gunk. Because everything
has its own DNA or other nano-scale label, robots sort the debris and return it to its
designated location, or send it for recycling if it was destroyed. In a few days, the gunk is
gone. Bloated nanites have been transported to forests, where they fertilize the soil with
their load of nutrients. (Posted on Tuesday, December 28,2004)



Nanotech might not be ready in time for the next tsunami.

A tsunami warning system is crucial of course to give people time to move the 1/2-
kilometer from the beach to the top of the hill. Even if there had been such a system in
place in the recent Asian tsunami, there are some islands where there isn't high enough
ground close enough to get to in time (Indonesia would have had less than 20 minutes
warning).


Using technology to prepare for future tsunamis. A possible scenario
Perhaps if sea levels continue to rise, a barrier of this type could be built in anticipation of
a tsunami as well and serve both purposes if built correctly?
GRAZING THE NANOGRASS:
Adaptable substance may cool computers and put a zoom lens in your cell phone.
A drop of water glides across the flat surface like quicksilver, moving effortlessly from
place to place as the surface is tilted. It's hard to believe that the little bead is water, for it
doesn't wet the surface as it races around, seemingly without friction.

The little drop in this impromptu laboratory demonstration isn't on an ordinary surface.
It's riding on "nanograss," a bed of upright silicon posts a thousand times thinner than a
human hair. Bell Labs, the research and development arm of Lucent Technologies Inc., is
betting that nanograss will find its way into commercial products ranging from low-
friction boat hulls to heat sinks for computer processors and batteries with a shelf life of
25 years. It will be one of the first nanoscale technologies commercialized by Bell Labs
and its partner, the New Jersey Nanotechnology Consortium (NJNC).

"Nanograss is a whole new class of structure, where we are nanoengineering the surface
of a material," says David Bishop, a research vice president at Bell Labs and president of
the NJNC. "By adjusting the area of these posts and their density, and how you pattern
them, you can engineer how the fluid interacts with the substrate. So you are not stuck
with what nature gave you, and you can do lots of amazing things."

It is also possible to alter the properties of nanograss on the fly by changing the
temperature, applying ultrasound or a small voltage, or other means. A voltage builds up
an electrical field at the tips of the nanograss, and that changes its wettability through an
effect called electrowetting.


                                  That could allow the electrodes and electrolytes in a
                                 battery to remain separated until the battery is needed,
                                 extending its shelf life indefinitely. Conventional
                                 batteries discharge at the rate of 3% to 5% a month, even
                                 when not in use. Nanograss batteries will cost less and have
                                 far higher power-to-weight ratios, researchers predict.



Other applications of nanograss include the following:

• Heat sinks for computer processors and other devices. "It's very hard to get high fluid
flows through small silicon channels; it kind of jams up," Bishop says. "But nanograss
allows much higher fluid flow because the liquid is only interacting with one-hundredth
as much surface."

Commercialization of the nanograss heat-sink idea is two to three years away, but Bell
Labs is about to sign a contract with a company to develop a "smart" heat sink that can
change its cooling properties as needs change, he says. The idea is noteworthy because
chipmakers have found that heat dissipation is one of the greatest obstacles to making
silicon circuits smaller than the current generation, at 90 nanometers.

• Liquid lenses. It's possible to construct tiny, cheap liquid lenses whose focal lengths
and other properties can be changed very quickly by the application of electrical fields.
Bishop predicts that disposable cameras and cell phones with zoom lenses based on this
idea could be available in a year.

• "Liquid photonics." In three to five years, nanograss might also go into switches,
power splitters, filters, multiplexes and other devices in order to manipulate light in ways
that are difficult to do by conventional means.

"Nanograss is an important technology because it combines a materials breakthrough
with electronic properties that enhance the material and allow it to be used as a platform
for a slew of applications," says Josh Wolfe, a managing partner at Lux Capital Group
LLC, a venture capital firm in New York.

Wolfe says such "hybridization of disciplines" is a defining characteristic of many
nanotech applications, and it allows for advancements that would have been impossible
in a world where scientists generally concentrated on just one field at a time.

MPhase Technologies Inc. in Norwalk, Conn., is working with Bell Labs and the NJNC
at Bell Labs' $400 million "nanofabrication laboratory" in Murray Hill, N.J., to develop
nanotech batteries. The parties will share any patents that result. MPhase will produce
some batteries itself and will license the technology to other battery makers, says Steve
Simon, the company's executive vice president for R&D.

MPhase will make conventional nonrechargeable batteries and "reserved" batteries --
those that don't combine the electrolyte and electrodes until the battery is needed, Simon
says. The batteries will be used in military applications in 2006 and in commercial
devices, such as cell phones, handheld devices and notebook computers, in about three
years. Preliminary benchmark data from mPhase shows that the batteries will have three
to four times the power-to-weight ratio of ordinary AA batteries.

That's what Bell Labs' David Bishop calls nanotechnology. "Physics, chemistry and
biology all intersect at the nanoscale, and all have gotten there simultaneously," he says.

"Nanotech is about bringing engineering precision and discipline to a world where we
know lots of interesting things happen at the nanoscale, rather than wait 5 billion years
for something to evolve," he adds.

Lucent Technologies in 2003 established the New Jersey Nanotechnology Consortium, a
regional partnership of Bell Labs, the state of New Jersey and the New Jersey Institute of
Technology. The heart and soul of the consortium is Bell Labs' nanoscale fabrication
facility, which can take an idea from concept to commercialization.
The National Science Foundation estimates that that by 2015, nanotechnology will
generate $1 trillion in revenue in the U.S. "It's now at a few tens of billions a year, so
over the next 10 to 15 years, nanotech revenue will grow by a factor of 100," Bishop
says. "No other area of technology is likely to grow at that rate. It's got a little bit of the
feel of the gold rush."


Scientists at Bell Labs, the research and development arm of Lucent Technologies have
discovered an entirely new method to control the behavior of tiny liquid droplets by
applying electrical charges to specially engineered silicon surfaces that resemble blades
of grass. The new technique of manipulating fluids has many potential applications,
including thermal cooling of integrated circuits for powerful computers, novel photonic
components for optical communications, and small, low-cost "lab-on-a-chip" sensor
modules.

"Once in a while, we get a research breakthrough that has wide applicability across many
fields," said David Bishop, vice president of nanotechnology at Bell Labs and president
of the New Jersey Nanotechnology Consortium. "The techniques resulting from this
research might be applied to fields that range from optical networking and advanced
micro batteries to self-cleaning windshields and more streamlined boat hulls."

The advance that made this possible was a breakthrough technique that Bell Labs
scientists developed for processing silicon surfaces, so that these surfaces resemble a
lawn of evenly cut grass, with individual "blades" only nanometers in size. (A nanometer
is a billionth of a meter, roughly one hundred thousand times smaller than the diameter of
a human hair).

This new capability to process silicon surfaces to produce "nanograss" lets liquids
interact with surfaces in a novel way, thereby providing a way to precisely control their
effects. In everyday experience, fluids tend to wet surfaces and stick to them. For
example, a raindrop sticks to a car's windshield; when water is spilled, it splatters every
which way. The individual blades of the nanograss are so small, however, that liquid
droplets sit on top and can be easily maneuvered.

"Physically, this technique reduces the surface area that the droplet feels, and reduces the
interaction between the liquid and the substrate by a factor of a hundred to a thousand,"
said Tom Krupenkin, the Bell Labs scientist who led the research.

Krupenkin and his team coated the nanograss with a non-stick, water-repellent material,
and when the droplets are put on the surface, they can move about without wetting it. By
applying a small voltage, however, the team could tailor the behavior of droplets, making
them sink in and wet the surface as directed. The droplets also respond to a change in
temperature, allowing for thermal cooling applications.
"Such behavior may be harnessed to cool computer chips," Krupenkin said. "A droplet
could be sent to a hot spot on the chip, where it would sink in and absorb the heat, and
then go on its way, avoiding the expense and inefficiency of applying a coolant or a heat
sink to an entire chip."

Another application for this technique may be in optical networking. For example,
moving a droplet of fluid into a nanograss surface can alter the physical properties of the
transmitting medium through which light signals are sent, and this may lead to better
methods for optical switching. Novel optical components, such as filters, could be created
by moving the fluid into and out of nanograss areas, Krupenkin said.

Bell Labs and the New Jersey Nanotech Consortium are also exploring using the
technique to create powerful, next-generation reserve micro batteries. Conventional
batteries have electrochemical reactions proceeding at some level all the time, even when
batteries are not being used. Over time, the batteries degrade. By using the Bell Labs
technique to isolate the liquid electrolyte so that electrochemical reactions do not take
place until power is actually needed, nanograss-based micro batteries may be ideal for
long-term, higher capacity battery applications, especially where bursts of power are
needed. Examples would be sensors out in the field that only need a lot of power when
they detect something and need to transmit the information as a wireless signal.

Yet another application for the nanograss may be "lab-on-a-chip" devices. "Potentially,
one can envision lab-on-the-chip devices that use thousands of different reagents, each
deposited in a small spot at the bottom of the nanograss, thus providing novel devices for
combinatorial chemistry, genetic analysis, and so on," Krupenkin said. "Some other
possible applications where nanograss can be used may be for low-friction torpedoes,
self-cleaning windshields, and faster boats where the fluid-repellent properties of the
nanograss would be important."
Uniform that makes soldiers invisible in the works:

The Army is hunting for a new military uniform that can make soldiers nearly invisible,
grant superhuman strength and provide instant medical
care.


The Massachusetts Institute of Technology is up for the
task.

The school said Wednesday it has been awarded a five-
year, $50 million dollar grant to develop the armor, which
could detect threats and protect against projectiles and
biological or chemical weapons.

"We're not there yet, but it's not science fiction," said Ned
Thomas, director of the MIT-affiliated Institute for Soldier
Nanotechnologies.

                                                           An artist’s illustration
                                                           depicting the possible look of
                                                           the U.S armed forces battle
                                                           uniform of the future.


All this would be achieved by developing particle-sized materials and devices — called
"nanotechnology" — nestled into the uniform's fabric.

Supercharged shoes could release energy when soldiers jump, propelling them over a 20-
foot wall. Micoreactors could detect bleeding and apply pressure. Light-deflecting
material could make the suit blend in with surroundings.

MIT's research centers had been working on nanotechnology ideas long before getting
involved with the Army, but not with military applications in mind. But the groundwork
has been laid for revolutionary advances.`
CONCLUSION:
Nanotechnology is the creation of functional materials, devices and systems through
control of matter on the nanometer length scale (1-100 nanometers), and exploitation of
novel phenomena and properties (physical, chemical, biological, mechanical, electrical...)
at that length scale. For comparison, 10 nanometers is 1000 times smaller than the
diameter of a human hair. A scientific and technical revolution has just begun based upon
the ability to systematically organize and manipulate matter at nanoscale. Payoff is
anticipated within the next 10-15 years.

Why Nanotechnology at NASA?
     Advanced miniaturization is a key thrust area to
     enable new science and exploration missions


    - Ultrasmall sensors, power sources,
      communication, navigation, and propulsion
      systems with very low mass, volume and power
      consumption are needed

     Revolutions in electronics and computing will
     allow reconfigurable, autonomous, "thinking"
     spacecraft

     Nanotechnology presents a whole new spectrum
     of opportunities to build device components and
     systems for entirely new space architectures

    - Networks of ultrasmall probes on planetary
      surfaces

    - Micro-rovers that drive, hop, fly, and burrow

    - Collection of microspacecraft making a variety
      of measurements
BIBLIOGRAPHY:
BOOK REFERENCES:
1.THE WEEK
2.ELECTRONICS FOR YOU
3.SCIENTIFIC AMERICAN

INTERNET REFERENCES:
1.WWW.GOOGLE.COM
2.WWW.IPT.ARC.NASA.GOV

TELEVISION REFERENCES:
1.DISCOVERY CHANNEL DOCUMENTARIES
2.NDTV 24X7

				
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