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