Smaller is Better Source: BBC News Sci/Tech Scientists are dreaming of a day when making a new
computer display will be as easy as feeding plastic film through an
inkjet-style printer.
The printer would not be filled with ink but with a
chemical solution containing tiny components which organise themselves
into a useable, flexible display, delegates to the annual meeting of
the American Association for the Advancement of Science (AAAS) were
told.
This is the kind of long-term goal for researchers at
IBM, Sandia National Laboratories and elsewhere who are studying
nanotechnology - technology on the atomic scale.
The technology promises:
* blazingly fast and yet inexpensive computers
* "smart" fabrics that could open up millions of
nanoscale channels when a person was hot or close the channels in the
presence of a dangerous chemical
* nanoscale machines that could be injected into the
bloodstream for dialysis or drug delivery.
Smaller, faster, cheaper
Computer makers such as IBM are interested in the
technology because making smaller, faster and cheaper computers has
relied on the increasingly finer control of the structure of matter
for manufacturing, said Thomas Theis, the director of physical science
at IBM's Thomas J Watson Research Centre.
We need to learn how to better manipulate individual
atoms and their properties
To make the Hollerith Tabulating machine at the turn of
the last century, machinists had to manufacture parts with the
precision of a millimetre.
In 1960, computer makers could manufacture features for
solid-state electronics as small as 10 microns (a micron is a
thousandth of a millimetre).
And now computer chipmakers can etch microprocessor
features down to 0.1 of a micron.
Computer chips have become faster as they have become
smaller, but in 10 to 15 years, the lithographic techniques used now
to etch computer chips "run into fundamental problems. "The physics
don't work," Theis said.
Being able to build circuits and transistors atom by
atom might be one solution.
Cheating Moore's Law
The increasing speed of computing was first described by
Intel co-founder and now chairman emeritus, Gordon Moore, in the
1960s.
He said that the speed of processors would double about
every 18 months, but as chips became faster, he also saw that it would
be increasingly expensive to fabricate them.
Some bacteria could show us how to synthesise tiny
crystals.
At some point, the cost of fabrication might exceed any
reasonable price that manufacturers could charge for them, making the
technology economically infeasible.
Researchers have learned how to move individual atoms,
building nanoscale structures atom by atom, but "the methods are
expensive and tedious," Theis said.
The challenge is to find a way to make nanotechnology
cost-effective, and researchers already have examples of efficient and
cost effective nanoscale manufacturing: nature.
Snowflake analogy
The human body and our own DNA show how a complex system
can be made atom by atom. "We need to learn to do some of the tricks
that nature does," the IBM researcher said.
They are not looking to make biological computers but
rather by using biological techniques to make computers out of
silicon.
The right mix of chemicals and the fine control of
conditions such as temperature, humidity and pressure, might be able
to allow for the self-assembly of complex structures.
He gave the analogy of snowflakes, which are amazingly
complex and exhibit almost limitless differentiation. This is achieved
by only slight changes in pressure and humidity.
Learning how these conditions and others can affect
chemicals, scientists hope to coax them into assembling themselves
into crystals and other useful materials. Computer makers see
nanoscale technologies as key to the future of information technology.
As computers become faster, smaller and less expensive,
Theis said they could tackle bigger problems, make their way into a
host of new devices and better interact with their human users.
by Kevin Anderson
Washington
February 20, 2000