Nanotechnology: How the Science of the
Very Small Is Getting Very Big

o
Play or download an MP3 of this story
Explorations - Download MP3
Listen
o
Playlist
(VOICE ONE:
I’m Steve Ember.
VOICE TWO:
And I’m Faith Lapidus with Explorations in VOA Special English. Today we tell
about one of the most important research fields in technology. It is called
nanotechnology. It is the science of making things unimaginably small. But there
is nothing small about the problems that scientists hope nanotechnology will
solve.
(MUSIC)
VOICE ONE:
Nanotechnology gets its name from a measure of distance. A nanometer, or
nano, is one-thousand-millionth of a meter. This is about the size of atoms and
molecules. Nanotechnologists work with materials this small.
Many experts credit the idea to physicist Richard Feynman. In nineteen fifty-nine,
this Nobel Prize winner gave a speech. He called it “There’s Plenty of Room at
the Bottom.” Mister Feynman discussed the theory that scientists could make
devices smaller and smaller -- all the way down to the atomic level.
Although he did not use the word nanotechnology, the speech got many
scientists thinking about the world of the very small. But for years this idea
remained only a theory.
VOICE TWO:
At the time, no way existed to record structures the size of molecules. Not even
electron microscopes could do the job. But as the nineteen eighties began, two
researchers found a way. Gerd Binnig and Heinrich Rohrer worked at a
laboratory in Zurich Switzerland. They worked for IBM, the American company
International Business Machines.
They invented what they called a scanning tunneling microscope. This permitted
scientist to observe molecules and even atoms in greater detail than ever before.
VOICE ONE:
Once they could see nano-sized structures, the next step for scientists was to
find a way to create their own. By the middle of the nineteen eighties, scientists
had increased their research on carbon. They were interested in the ability to
use this common element to make nano-sized structures. Carbon had already
been engineered in chemical reactions to make long poly-carbon chains. Today,
the result of carbon chemical engineering is everywhere -- in the form of plastic.
Scientists in the nineteen eighties wanted to create nano-structures from carbon
atoms. In nineteen eighty-five, Robert Curl, Harold Kroto and Richard Smalley
succeeded. They aimed a laser at carbon. This powerful light caused some of
the carbon to become a gas.
The scientists cooled the gas to an extremely low temperature. Then they looked
at the carbon material that remained. They found, among several kinds of
carbon, a molecule of sixty atoms -- carbon sixty.
VOICE TWO:
Carbon sixty is a group of tightly connected carbon atoms that forms a ball. It is a
very strong structure. This is because all the atoms share any loose electrons
that might take part in chemical reactions with other atoms. This kind of
molecular carbon can also appear with different numbers of carbon atoms. There
is also carbon seventy, for example.
For their work, Robert Curl, Harold Kroto and Richard Smalley received the Nobel
Prize in Chemistry in nineteen ninety-six.
(MUSIC)
VOICE ONE:
The next nano-structure development came in nineteen ninety-three. Japanese
scientist Sumio Iijima of the company NEC developed carbon nanotubes. These
nano-sized objects are really six-sided atomic structures connected to form a
tube. They are extremely strong. Scientists believe that someday nanotubes
could replace the carbon graphite now used to make airplane parts.
Soon after this discovery, researchers started to think about using nanotubes to
build extremely small devices.
In two thousand three, IBM announced that it had made the world's smallest
light. Researchers used a carbon nanotube attached to a silicon base. They
sent opposing electrical charges down the tube. The reaction between the
charged particles produced an extremely small amount of light. IBM says the
wavelength of light produced could be used in communications.
VOICE TWO:
Nanotubes appear to have many different uses. Scientists at the University of
Texas at Dallas have developed a way to make a flat material, or film, out of
nanotubes. The researchers create the super thin film by chemically growing
nanotubes on a piece of glass. They use another piece of sticky material to
remove the film of nanotubes from the glass. When the film is finished, it is only
fifty nanometers thick. That is about one one-thousandth the width of human
hair.
The material is extremely strong and it carries electricity as well. Researchers
think the nanotube material could be used to make car windows that can receive
radio signals. They also believe it could be used to make solar electricity cells,
lights or thin, moveable displays that show pictures like a television.
VOICE ONE:
Nano-materials are already being used in some products. For example,
materials using mixtures of nano-materials are being used to make sporting
goods like tennis balls and tennis rackets better.
Soon, nano-materials could be used to improve devices that reduce pollution
released by cars. Similar technology could be used to warn of the presence of
poisonous molecules in the air.
(MUSIC)
VOICE TWO:
Computer scientists hope developments in nanotechnology will help break
barriers of size and speed. In nineteen sixty-five, electronics expert Gordon
Moore recognized that computer chips, the engines that drive computers, would
quickly grow in power.
He even thought of a way to measure this progress. He said researchers would
double the number of tiny transistors on a computer chip about every two years.
A transistor is a device that controls electrical current.
That statement is known as Moore’s law. It has proved correct for more than forty
years. Mister Moore would go on to help start the company Intel, one of the
world’s leading computer chip makers. And Moore’s law is one of the most talked
about scientific barriers.
VOICE ONE:
In nineteen seventy-one, Intel created a computer chip containing two thousand
three hundred transistors. In two thousand four, Intel made a chip with five
hundred ninety-two million transistors. But current technology has reached its
limit. The next jump to one thousand million transistors will require new
discoveries in nanotechnology.
Researchers are trying to solve the problems of creating nano-sized transistors.
In two thousand two, IBM announced that it had created the world’s smallest
transistor based on the element silicon. IBM said the transistor was four to eight
nanometers thick.
In two thousand five, researchers for the company Hewlett Packard wrote about
the problems of creating nano-transistors in the magazine Scientific American.
They said transistors are often measured by the distance between the middle of
two current-bearing wires. Their nano-wire transistor measured thirtynanometers in size. They said the smallest transistor currently used in a
computer is ninety nanometers. But making nano-transistors small enough to
meet the demands of Moore’s law may be years in the future.
(MUSIC)
VOICE TWO:
Although nanotechnology is exciting, there are concerns about the safety of
super small structures. Scientists and environmental activists worry that nanomaterials could pass into the air and water causing health problems.
There is reason for concern. A study by NASA researchers found that nanoparticles caused severe lung damage to laboratory mice. Other studies suggest
that nano-particles could suppress the growth of plant roots or could even harm
the human body’s ability to fight infection.
VOICE ONE:
The Environmental Protection Agency says there is not much known about the
effects of nano-structures in the environment. This is because the laws of
physics do not work in the same way at the level of the extremely small. The
EPA recognizes that this could mean that there are unknown health risks
involved in nanotechnology.
The government is expected to spend about thirty nine million dollars on research
meant to investigate the health risks of nano-materials. But that is less than four
percent of total government spending, which will be more than one thousand
million dollars this year.
Many environmental groups say at least ten percent of that total is needed. They
say private industry needs to spend more on safety research. And, they say, the
government needs to develop rules for nano-materials, which are already being
made in hundreds of places around the country.