High-speed graphene transistors could mean faster mobiles, computers

A group of UCLA researchers has fabricated the fastest graphene transistor to date, which could translate into faster electronic devices such as radios, computers and mobiles.

Graphene, a one-atom-thick layer of graphitic carbon, has the highest known carrier mobility making it a great candidate for high-speed radio-frequency electronics.

The UCLA team has developed a new fabrication process for graphene transistors using a nanowire as the self-aligned gate. Self-aligned gates are devices used to amplify and switch electronic signals and were developed to deal with problems of misalignment encountered because of the shrinking scale of electronics.

"First, it doesn't produce any appreciable defects in the graphene during fabrication, so the high carrier mobility is retained,” Nature quoted Xiangfeng Duan as saying.

“Second, by using a self-aligned approach with a nanowire as the gate, the group was able to overcome alignment difficulties previously encountered and fabricate very short-channel devices with unprecedented performance," he added.

These advances allowed the team to demonstrate the highest speed graphene transistors to date, with a cut-off frequency up to 300 GHz.

"We are very excited about our approach and the results, and we are currently taking additional efforts to scale up the approach and further boost the speed." said Lei Liao, a postdoctoral fellow at UCLA.
The paper is published September 1 in the journal Nature.