London, January 16 (ANI): Scientists have found a way to build better carbon nanotubes, which would help transistors to shrink smaller than silicon ones.Reports indicate that engineers are running out of ways to shrink silicon transistors and cram more power into chips.
Carbon nanotubes had been considered a potential saviour, but making transistors with them has proved to be difficult.
Performance in such transistors is limited by an effect that creates an electrical barrier at each point a nanotube joins any metal, impeding current flow.
This seemed a deal-breaker because a nanotube in a transistor must connect to two metal electrodes, with a third "gate" electrode placed nearby.
Using fatter nanotubes reduced the size of the electrical barriers, but goes against the computer scientists' goal of constantly making things smaller.
Now, Aaron Franklin and colleagues at IBM's Watson Research Center in Yorktown Heights, New York State, have found a way to use thinner tubes to build a competitive nanotube transistor.
Franklin's team placed the gate electrode, which controls the transistor, below the nanotube instead of in its usual position above it.
This makes it possible to position the two closer together, and increases the gate's influence on electrons inside the nanotube, enabling them to punch through the electronic barriers.
Moving the nanotube and gate electrode closer together also makes it possible to shrink the device's length down to 15 nanometres.
"That's about half the length of the best silicon technology on the market today," said Franklin.
"This is great work that helps shed light on the scaling of carbon nanotube transistors," said Yu Cao at Arizona State University in Tempe. (ANI)