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Updated: Apr 24, 2026

Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Exceptional charge transport properties of graphene on germanium
Francesca Cavallo1, Richard Rojas Delgado, Michelle M Kelly
1University of Wisconsin-Madison , Madison, Wisconsin 53706, United States .
Abstract:
The excellent charge transport properties of graphene suggest a wide range of application in analog electronics. While most practical devices will require that graphene be bonded to a substrate, such bonding generally degrades these transport properties. In contrast, when graphene is transferred to Ge(001) its conductivity is extremely high and the charge carrier mobility derived from the relevant transport measurements is, under some circumstances, higher than that of freestanding, edge-supported graphene. We measure a mobility of ∼ 5 × 10(5) cm(2) V(-1) s(-1) at 20 K, and ∼ 10(3) cm(2) V(-1) s(-1) at 300 K. These values are close to the theoretical limit for doped graphene. Carrier densities in the graphene are as high as 10(14) cm(-2) at 300 K.
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