Using grazing-incidence x-ray diffraction and scanning tunneling microscopy (STM), we show that the thermal decomposition of an electronic-grade wafer of 6H-SiC after annealing at increasing temperatures TA between 1080 and 1320 °C leads to the layer-by-layer growth of unconstrained, heteroepitaxial single-crystalline graphite. The limited width of the in-plane diffraction rod profiles of graphite reveals large terraces, with an average size larger than 200 Å and a very small azimuthal disorientation. The overlayer is unstrained and adopts the crystalline parameter of bulk graphite even at the smallest coverage studied, which corresponds to a single graphene plane, as inferred from the flat out-of-plane diffraction profile. By increasing TA, additional graphene planes can be grown below this graphite layer from the solid-state decomposition of SiC, forming the AB stacking of Bernal graphite. A C-rich precursor is evidenced in STM by an intrinsic (6×6) reconstruction made of ordered ring or starlike structures. The resulting epitaxial film is indistinguishable from a bulk graphite single crystal.

This paper reports on Au(111) vicinal surfaces, either regularly stepped surfaces, reconstructed or not, or periodically faceted surfaces, which are well suited to be used as templates for organized growth of clusters. Angles of misorientation with respect to the (111) plane lie between 1 • and 12 • and two opposite azimuths are considered: (i) [211], that leads to steps with {100} microfacets, and (ii) [211], that leads to steps with {111} microfacets. The behaviour of the Au(111) reconstruction in the vicinity of steps depends drastically on the step microstructure, and this is a key point for understanding the various periodic morphologies existing on Au(111) vicinal surfaces. The interaction between the reconstruction and the close-packed steps of the Au(111) surface is interpreted in terms of the relative stability of both types of step. Self-organized morphologies between 10 and 100 nm are interpreted within the framework of elastic theory and by pointing out the crucial role played by the atomic boundary energy term. The microscopic origin of faceting is discussed, proposing two different models depending on each azimuth. Then, we illustrate the use of Au(111) vicinal surfaces as templates for growing long range ordered nanostructures. Examples are given in the case of cobalt growth.

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