Regensburg 2013 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

O: Fachverband Oberflächenphysik

O 23: Graphene: Electronic Properties and Transport (jointly with HL, MA and TT)

O 23.11: Vortrag

Montag, 11. März 2013, 18:30–18:45, H17

Graphene on boron nitride microwave transistors driven by graphene nanoribbon back-gates — Christian Benz^1,2, •Maximilian Thürmer¹, Fan Wu¹, Zeineb Ben Aziza¹, Jens Mohrmann¹, Hilbert von Löhneysen^1,2,3,4, Kenji Watanabe⁵, Takashi Taniguchi⁵, and Romain Danneau^1,2 — ¹Institute of Nanotechnology, Karlsruhe Institute of Technology, Germany — ²Institute of Physics, Karlsruhe Institute of Technology, Germany — ³DFG Center for Functional Nanostructures, Karlsruhe Institute of Technology, Germany — ⁴Institute for Solid-State Physics, Karlsruhe Institute of Technology, Germany — ⁵Advanced Materials Laboratory, National Institute for Materials Science, Tsukuba, Japan

We have designed ultra-thin graphene microwave transistors by using pre-patterned metal or graphene nanoribbon back-gates and hexagonal boron nitride (h-BN) as a dielectric substrate. Despite the inhomogeneities induced by the graphene transfer process, we show that it is possible to operate these types of devices across a broad range of microwave frequencies. For the graphene nanoribbon gates, we observe a deviation of the current gain from the usual 1/f trend that can be attributed to the large gate resistance of these systems as we demonstrate with our small-signal model. The scattering parameter analysis shows a very limited back-action from the channel onto the graphene nanoribbon gates. Our work thus proves that graphene microwave transistors could be driven by graphene nanoribbon gates.