The former TGM3-beamline of BESSYI was rebuilt at the 1.5 GeV storage ring facility DELTA at the University of Dortmund, Germany. This dipole beamline provides synchrotron radiation between 6 and 200 eV for photoelectron spectroscopy and Fermi-surface-mapping experiments. The former beamline design was kept, especially the optical layout. The vacuum system was completely redesigned, except the mirror and slit chambers. For the beamlinesetup at DELTA, the focusing mirror is mounted inside the radiation wall shielding, therefore a motorisation of the mirror movements was necessary. The thermal load on the optical elements at DELTA is much higher than the previous load at BESSYI because of the higher electron beam energy in the storage ring. Therefore a watercooling of the first mirror had to be integrated and a complete new design of the chamber for the focusing mirror was necessary. In order to integrate the monochromator into the beamline control system, the monochromator control system had to be replaced. First commissioning of the beamline will be performed in 2006.

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We report on a study of the Co intercalation process underneath the R30° reconstructed 6H-SiC(0001) surface for Co film-thicknesses in a range of 0.4–12 nm using a combination of surface sensitive imaging, diffractive, and spectroscopic methods. In situ photoemission electron microscopy reveals a dependence of the intercalation temperature on the Co film-thickness. Using low energy electron diffraction and photoemission spectroscopy (XPS), we find that the SiC surface reconstruction is partially lifted and transformed. We show that the R30° reconstruction does not prevent silicide formation for Co film-thicknesses  ≥0.4 nm according to XPS and x-ray absorption spectra. Our results indicate that the silicide formation is self-limited to a thin interface region and is followed by Co intercalation between graphene and silicide. Furthermore, we analyze the magnetic properties using x-ray magnetic circular dichroism at the Co L-edge. In-plane magnetization is observed for all analyzed film-thicknesses. For ultra-thin Co films, self-assembled magnetic wires with a width of the order of 100 nm form at the step-edges.