A low-pressure oxygen plasma oxidized Cu(100) and Cu(111) surfaces at room temperature. The time-dependent evolution of surface structure and chemical composition is reported in detail for a range of exposure times up to 30 min.

The industrial realization of graphene has so far been limited by challenges related to the quality, reproducibility, and high process temperatures required to manufacture graphene on suitable substrates. We demonstrate that epitaxial graphene can be grown on transition-metal-treated 6H-SiC(0001) surfaces, with an onset of graphitization starting around 450−500 °C. From the chemical reaction between SiC and thin films of Fe or Ru, sp 3 carbon is liberated from the SiC crystal and converted to sp 2 carbon at the surface. The quality of the graphene is demonstrated by using angle-resolved photoemission spectroscopy and low-energy electron diffraction. Furthermore, the orientation and placement of the graphene layers relative to the SiC substrate are verified by using angle-resolved absorption spectroscopy and energy-dependent photoelectron spectroscopy, respectively. With subsequent thermal treatments to higher temperatures, a steerable diffusion of the metal layers into the bulk SiC is achieved. The result is graphene supported on magnetic silicide or optionally, directly on semiconductor, at temperatures ideal for further large-scale processing into graphene-based device structures.

Establishing the rather complex correlation between structure and charge transfer in organicorganic heterostructures is of utmost importance for organic electronics and requires spatially resolved structural, chemical and electronic details. Insight in this issue is provided here by combining atomic force microscopy, Kelvin probe force microscopy, photoemission electron microscopy and low-energy electron microscopy for investigating a case study. We select the interface formed by pentacene (PEN), benchmark among the donor organic semiconductors, and a p-type dopant from the family of fluorinated fullerenes. As for Buckminsterfullerene (C60), the 2 growth of its fluorinated derivative C60F48 is influenced by thickness and crystallinity of the PEN buffer layer, but the behaviour is markedly different. We provide a microscopic description of the C60F48/PEN interface formation and analyse the consequences in the electronic properties of the final heterostructure. For just one single layer of PEN, a laterally complete but non-compact C60F48/PEN interface is created, importantly affecting the surface work function. Nonetheless, from the very beginning of the second layer formation, the presence of epitaxial and non-epitaxial PEN domains dramatically influences the growth dynamics and extremely well packed twodimensional C60F48 islands develop. Insightful element maps of the C60F48/PEN surface spatially resolve the non-uniform distribution of the dopant molecules, which leads to a heterogeneous work function landscape.

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Spatio-temporal nonuniformities in H 2 oxidation on individual Rh( h k l ) domains of a polycrystalline Rh foil were studied in the 10 –6 mbar pressure range by photoemission electron microscopy (PEEM), X-ray photoemission electron microscopy (XPEEM), and low-energy electron microscopy (LEEM). The latter two were used for in situ correlative microscopy to zoom in with significantly higher lateral resolution, allowing detection of an unusual island-mediated oxygen front propagation during kinetic transitions. The origin of the island-mediated front propagation was rationalized by model calculations based on a hybrid approach of microkinetic modeling and Monte Carlo simulations.