Epitaxial graphene field-effect transistors on silicon substrates

We have fabricated and characterized the field effect transistors having an 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 layer on Si substrates and subsequently to anneal them in UHV to make few layers of graphene on the sample surface. Backgate transistors were able to be formed by using the SiC layer as a gate insulator. Although the gate-leakage current is not negligible, the drain current modulation by means of the gate voltage is confirmed by extracting the channel current from the total drain current. A new evaluation method of the area contact resistance between graphene and metal is also proposed.