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Interfacial interactions at graphene/metal and graphene/dielectric interfaces are likely to profoundly influence the electronic structure of graphene. We present here the first angle-resolved near-edge X-ray absorption fine structure (NEXAFS) spectroscopy study of single-and bilayered graphene grown by chemical vapor deposition on Cu and Ni substrates. The spectra indicate the presence of new electronic states in the conduction band derived from hybridization of the C-π network with Cu and Ni d-orbitals. In conjunction with Raman data demonstrating charge transfer, the NEXAFS data illustrate that the uniquely accessible interfaces of two-dimensional graphene are significantly perturbed by surface coatings and the underlying substrate. NEXAFS data have also been acquired after transfer of graphene onto SiO 2 /Si substrates and indicate that substantial surface corrugation and misalignment of graphene is induced during the transfer process. The rippling and corrugation of graphene, studied here by NEXAFS spectroscopy, is thought to deleteriously impact electrical transport in graphene.SECTION Surfaces, Interfaces, Catalysis G raphene, a one-atom-thick, two-dimensional (2D) electronic system exhibiting a cornucopia of quantum transport phenomena, is constituted from a single layer of carbon atoms tightly packed within a honeycomb lattice.1-3 Recent advances in the wafer-scale fabrication of graphene by chemical vapor deposition (CVD) methods inspire confidence that it may be possible to harness the remarkable electronic structure of graphene for applications in microelectronics and quantum logic devices. [4][5][6][7] In particular, the massive room-temperature mobilities of charge carriers in graphene 8,9 portends the possible use of this material in ultrahigh frequency transistors with an operational regime extending to the terahertz range.2 The large phase coherence length and room-temperature ballistic conduction observed across micrometer-scale dimensions further tantalizes with possibilities for applications in spin-logic architectures. 10,11 Much of the novel transport phenomena observed for graphene is derived from its unique electronic structure wherein electrons propagating through the honeycomb lattice behave as massless and chiral Dirac fermions, and the valence and conduction bands touch at conical Dirac points with a remarkable linear energy dispersion within (1 eV of the Fermi energy. 3As graphene transitions from being merely an object of academic curiosity to real device applications, there is considerable interest regarding modifications of the characteristic graphene electronic spectrum when graphene is interfaced with other materials including metals and dielectrics.

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The superior transport properties of III-V materials makes them attractive choices to enable improved performance at low power. This paper examines the module targets and challenges for III-V materials to be successfully integrated for high performance/low power logic at or beyond the 11 nm technology node. A VLSI compatible, self-aligned, III-V on 200mm Si MOSFET process flow is presented using an industry standard toolset. Statistically significant data shows that III-V devices can be processed on a Si line with controlled contamination, good uniformity and yield. The Lg = 500 nm device has a drive current of 471 µA/µm (Vgs = Vds = 1V) and intrinsic transconductance of 1005 µS/um.