Billions of tiny mechanical levers could be used to store songs on future MP3 players and pictures on digital cameras.
Researchers at a Dutch company have already demonstrated that miniscule
mechanical switches can be used to store data using less power than existing
technologies and with greater reliability.
Nanomech memory, developed by Cavendish Kinetics in the Netherlands, stores data
using thousands of electro-mechanical switches that are toggled up or down to
represent either a one or zero as a binary bit. Each switch is a few microns long
and less than a micron wide - roughly a hundred times smaller than the width of a
Existing computer memory typically stores data as an electrical or magnetic
charge. Cavendish Kinetics claims Nanomech memory can read and write data using
100 times less power than such systems, and works up to 1000 times faster. It is
also much more resilient to both temperature and radiation, the company claims.
Nanomech memory incorporates hundreds of thousands of conductive metal levers,
each just a few microns long. These are created by lithographically etching a
design onto a template and then chemically dissolving away unwanted layers.
Introducing a miniscule voltage to an electrode below a lever causes it to bend
forwards until it makes contact. Thanks to intermolecular forces on this scale,
once flipped, a lever will also maintain its position, even when the voltage is
switched off. The trick can be reversed by applying voltage to an electrode on
the other side of the lever. And the state of each switch flips can be sensed
easily by the electrodes themselves.
Repeating the feat across thousands of switches makes it possible to store
something as complex as a computer program in Nanomech memory.
Cavendish Kinetic has so far developed a unit capable of storing 256 kilobytes of
data, or around two million individual bits. This is suitable for simple
microcontrollers - the tiny computers used to operate commonplace electric motors
found, for example, in cars and consumer electronics products.
But eventually the company hopes to stack many more levers together, boosting
memory capacity to several gigabytes. "That's the long term aim," says Charles
Smith at Cambridge University, UK, who is a chief technology officer at Cavenish
Kinetics. "We want to put millions and millions on an individual chip."
This should make Nanomech memory a viable solution for portable music players and
digital cameras. And it could improve battery life dramatically.
"The big growth area for large scale non-volatile memory devices is portable
consumer applications, such as iPods and cameras," says Jim Miles, another
nanotechnology researcher at Manchester University, UK. "And for these devices,
power consumption is the big issue."
Miles, however, points out that it is vital to be able to repeatedly read and
write to this type of memory. "It's important to know rewrite speeds as well as
how many rewrite cycles they can survive," he says.
Smith says the first increased capacity Nanomech chips should be available by the
end of 2006. He adds that the memory technology's resilience to radiation should
also make it suitable for use aboard satellites and other spacecraft. This is
because cosmic radiation can cause space-borne computers to suddenly malfunction
by flipping bits stored in memory.