The effects of dielectric layers on SiC based epitaxial graphene in transistor applications

By characterizing the mobility of Si-face/C-face of SiC graphene before and after stacking the layer of HfO₂ with a polyvinyl alcohol (PVA) treatment on the device active layer, we have explored the properties of SiC based epitaxial graphene and the effects of the dielectric film with PVA treatment. Epitaxial graphene grown on the carbon face produces a higher mobility than film grown on the silicon face. Also, the mobility, in the presence of the PVA treatment, improves after the deposition of gate dielectrics: ~20% in C-face graphene and ~100% in Si-face graphene. This is unlike the degradation normally observed with dielectric/graphene systems.