High Mobility Epitaxial Graphene for Carbon-based Nanoelectronics

Epitaxial graphene has demonstrated a great potential for carbon-based electronic. Multiple nanoscale devices can be patterned on a scalable platform with high electronic mobility, large conductivity, and conductance modulation by an electrostatic gate. High quality seamless epitaxial graphene layers are grown on the entire surface of SiC substrates by thermal decomposition of the SiC crystal. For multilayer epitaxial graphene grown on the 4H-SiC (000-1) surface, transport and spectroscopy measurements demonstrate an effective decoupling of the adjacent graphene layers due to a non-graphitic ordered rotational stacking. Large switching ratios require a band gap but graphene is a gapless semimetal. Transport gaps have been demonstrated in chemical functionalized graphene and in narrow ribbons. But patterning techniques severely degrade graphene. Transport data on narrow graphene ribbons directly grown on silicon carbide substrate step edges at high temperature indicate reduced edge scattering and open the way to non diffusive electronics.