Graphene-Semiconductor Contact
A systematic treatment of graphene-semiconductor junction is presented. Finite density of states at the Fermi level of graphene leads to exotic electronic properties at graphene-semiconductor interface. Quite generally, the Schottky-Mott limit and the sum rule of barrier heights are violated due to the internal potential of graphene. By merging the principal characteristics of semiconductor-semiconductor and metal-semiconductor junctions, the graphene-semiconductor contact may be considered as an archetype of unprecedented \emph{semimetal-semiconductor junction}. Generalized interface equations disclose the coupling of junction characteristics with the density of charge carriers in graphene. It will be shown that the well-known effect of tunable barrier height is directly related to the junction capacitance. Furthermore, the relative impact of image-force effect in the presence of barrier tunability is investigated. Experimental methods to gain built-in potential, barrier height, and capacitance of the junction are discussed in detail. Also the development of strong inversion layer at the interface of graphene-silicon samples is uncovered by analyzing experimental data.