Electron transport chain

Quantum mechanics

Resist

Materials science

Graphene

Layer (electronics)

Etching (microfabrication)

Biochemistry

Physical chemistry

Physics

Nanotechnology

Electron mobility

Electron-beam lithography

Chemistry

Cathode ray

Electrode

Electron

Optoelectronics

Solid State Communications

We have achieved mobilities in excess of 200,000 cm 2 V −1 s −1 at electron densities of ∼2 ×10 11 cm −2 by suspending single layer graphene. Suspension ∼150 nm above a Si/SiO 2 gate electrode and electrical contacts to the graphene was achieved by a combination of electron beam lithography and etching. The specimens were cleaned in situ by employing current-induced heating, directly resulting in a significant improvement of electrical transport. Concomitant with large mobility enhancement, the widths of the characteristic Dirac peaks are reduced by a factor of 10 compared to traditional, nonsuspended devices. This advance should allow for accessing the intrinsic transport properties of graphene.

Ultrahigh electron mobility in suspended graphene