A major technological challenge is the finding of a new material for the postsilicon CMOS era. Graphene exhibits the excellent properties of carbon nanotubes (CNT), while not suffering from placing and scalability problems. Epitaxial graphene is the most viable candidate for high-speed low power nano-electronics device applications as recognized by the industry. An almost unexplored avenue for graphene is ballistic nanoelectronics. Pristine CNTs are known to be ballistic conductors even at RT. Graphene ribbons have similar properties and are thus interesting for all-graphene circuitry, for they are claimed to have better mobility and stand higher current densities than Cu wires.
Graphene nanoribbons can be produced in epitaxial graphene by non‐lithographic techniques on the sidewall of pre-etched SiC steps. This technique is scalable as already demonstrated by the fabrication of 10,000 transistors on a single chip. Moreover, transport data suggest smooth edges since disordered-related effects (localization, transport gap) are not observed. These ribbons may be the needed breakthrough in graphene electronics, opening new possibility of ballistic transport, non linear effect in ballistic junctions and new all-graphene interconnects. This opens the way for electronics based on ballistic transport and coherent effects, which cannot be realized in conventional semiconductors. The primary goal of this project is thus to study graphene nanoribbons grown on SiC sidewalls, and compare them with lithographically etched ribbons. Metal contacts on graphene, a key issue to any device fabrication will also studied. The main objective of CoRiGraph project is to study open questions on graphene sidewall nanoribbons and on metal/graphene interfaces about their atomic and electronic structure, which can be properly addressed with the complementary set of experimental techniques (ARPES, STM/STS, STEM) and calculations (quantum transport) available at the consortium.