Epitaxial graphene field effect transistors on silicon substrates

We have fabricated and characterized the field effect transistors having epitaxial-graphene channel grown on Si substrates. Epitaxial graphene is usually formed on SiC substrates by ultrahigh-vacuum (UHV) annealing. We used an approach to grow 3C-SiC(111) on Si substrates and subsequently to anneal it in UHV to make few layers of graphene on the sample surface. Backgate transistors using the SiC layer as a gate insulator was characterized. Although significant gate leakage current is observed, the drain current modulation by the gate voltage is confirmed by extracting the channel current from the total drain current. The drain saturation current of the graphene-channel transistors is in the order of mA/mm due to the large contact resistance that should be minimized in future study.