Top-gated, few-layer graphene field-effect transistors (FETs) fabricated on thermally decomposed semi-insulating 4H-SiC substrates are demonstrated. Physical vapor deposited SiO2 is used as the gate dielectric. A two-dimensional hexagonal arrangement of carbon atoms with the correct lattice vectors, observed by high-resolution scanning tunneling microscopy, confirms the formation of multiple graphene layers on top of the SiC substrates. The observation of n-type and p-type transition further verifies Dirac Fermions' unique transport properties in graphene layers. The measured electron and hole mobilities on these fabricated graphene FETs are as high as 5400 and 4400cm2/Vs, respectively, which are much larger than the corresponding values from conventional SiC or silicon.
Applied Physics Letters
- Pub Date:
- March 2008
- Field effect devices;
- Condensed Matter - Mesoscale and Nanoscale Physics;
- Condensed Matter - Materials Science
- Applied Physics Letters 92, 092192 (2008)