24 April 2012

High Voltage Gain realized in Graphene Transistors

Researchers from AMO GmbH and the University of Pisa recently managed to increase the intrinsic voltage gain in Graphene field effect transistors significantly.
Thus, the researchers took an important step towards the realization of Graphene-based circuits for analog high frequency applications.

Within the last couple of years, researchers from all over the world have hunted for higher operation frequencies in Graphene-based field effect transistors in order to surpass the frequency limitations of state-of-the-art-technologies. The intrinsic voltage gain, however, which represents another important quantity for analog applications, has lagged completely in most works. Within this work, researchers could realize Graphene transistors with a voltage gain of up to 35, a 6-fold improvement compared to the present state-of-the-art. This could be reached by using bilayer Graphene, where a small band-gap of 100 meV was introduced. In an interview, Tomas Palacios, IEEE Spectrum Professor at the MIT, calls the work "an important step in the direction of improving the performance of Graphene amplifiers." The complete story can be found at the homepage of IEEE Spectrum.

 

 

The work was financially supported by the German Science Foundation "DFG" unter contract number BA 3788/2-1 ("Ultragraphen"), by the European Union under contract number 215752 ("GRAND"), and by the Italian MIUR-PRIN project "GRANFET" (Prot. 2008S2CLJ9).

A publication of the research results appeared in the renowned journal "Nano Letters": Current Saturation and Voltage Gain in Bilayer Graphene Field Effect Transistors, B. Szafranek, G. Fiori, D. Schall, D. Neumaier, and H. Kurz, Nano Letters 12, 1324 (2012). DOI: 10.1021/nl2038634

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