IBM researchers have discovered a way to use graphite effectively in building nanoelectonic circuits vastly smaller than those in silicon-based computer chips.
Graphite, the same material found inside pencils, has promise as a much smaller replacement for today's silicon transistors. But a problem occurs when the material is formed into the single sheet of carbon molecules known as graphene: The smaller the sheet, the more electrical noise, or interference, occurs from signals bouncing around in the material as a current passes through it. The IBM researchers added a second sheet of graphene that reduces the interference significantly.
"The effect of noise…is exaggerated at the nanoscale because the dimensions are approaching the nearly smallest limits, down to only a handful of atoms, and the noise that is created can overwhelm the electrical signal that needs to be achieved to be useful," said IBM Researcher Dr. Phaedon Avouris, who leads IBM's exploration into carbon nanotubes and graphene. "To quote the famous physicist Rolf Landauer, at the nanoscale 'the noise is your signal'; in other words, you cannot produce any useful electronic device at the nanoscale if the noise is comparable to the signal you are trying to switch on and off."
The researchers' results were published in the journal Nano Letters.