Researchers at IBM demonstrated a radio-frequency graphene transistor with the highest cut-off frequency achieved so far for any graphene device – 100 billion cycles/second (100 GigaHertz). 
Graphene is a single atom-thick layer of carbon atoms bonded in a hexagonal honeycomb-like arrangement. IBM said this two-dimensional form of carbon has unique electrical, optical, mechanical and thermal properties and its technological applications are being explored intensely.
The wafer-scale, epitaxially grown graphene transistor was created with processing technology compatible to that used in advanced silicon device fabrication.
IBM said it is noteworthy that the frequency performance of the graphene device already exceeds the cut-off frequency of state-of-the-art silicon transistors of the same gate length (~ 40 GigaHertz).
http://www.ibm.com
