IBM has created a graphene-based transistor capable of operating at 100 gigahertz, which is more than twice as fast as silicon chips with speeds of 40 GHz using the same gate length. But unlike other high-speed transistors which are made from expensive semiconducting materials like indium phosphide, the graphene transistor will not require the same cooling.
IBM developed the graphene radio frequency transistors for the Defense Advanced Research Project Agency under its Carbon Electronics for RF Applications (CERA) program. The goal of the CERA program and of the IBM researchers is to get the speed of the graphene transistor to 1 THz.
The graphene transistor demonstrated in the research reported in Science had a gate length of 240 nanometers and by applying currently available lithographic techniques it will be possible to reduce that gate length to 35 nanomaters. This reduction in gate length should bring the 1 THz goal within reach.
As reported last week with IBM’s announcement of creating a band gap for graphene, Phaedon Avouris and his team of researchers at the IBM T.J. Watson Research Center in Yorktown Heights, New York, used a metal top-gate architecture employing a high-k dielectric oxide insulated from the graphene layer by a polymer for this high speed RF transistor.It would seem with these two announcements from IBM within a week of one another that graphene could move more quickly into commercial electronic applications than its carbon cousin, carbon nanotubes.
Dexter Johnson is a contributing editor at IEEE Spectrum, with a focus on nanotechnology.