Nanotube sparks could cool chips

As the transistors that make up a computer's logic circuits become smaller, they allow for more electrical signals between circuits in a given time period. This, in turn, creates more waste heat, which must be dissipated to keep the computer from overheating.

Researchers from Purdue University and have found a way to use carbon nanotubes to ionize air and generate minuscule air currents that can be used to cool computer chips. Nanotubes are rolled-up sheets of carbon atoms that can be smaller than the span of 10 hydrogen atoms in diameter.

The researchers were able to produce the ionizing effect by discharging electrons between nanotubes spaced 10 microns apart. The researchers created an air current by switching the voltage rapidly so that groups of ionized, or charged, air molecules were attracted to successive groups of nanotubes.

The researchers are working on making the concept practical. The goal is to produce a cooling device small enough to be integrated into a 10-millimeter by 10-millimeter chip, according to the researchers.

Computer chips have traditionally been cooled by fans and heat sinks. The researchers' device would be appropriate for laptop computers, which are traditionally cooled only by passive devices, and could open the way for higher-power chips to be used in laptops.

The method could be used practically in two years, according to the researchers.