Inhalt des Dokuments
- © Deutsche Forschungsgemeinschaft
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Technische Universität Berlin
Institut für Festkörperphysik
Arbeitsgruppe Prof. Dr. Norbert Esser
Sekr. EW 6-1
Functional Interfaces Lab
The joint project of TU Berlin and ISAS Interface Analytics Department is aimed at the structural analysis of functional interfaces and molecule terminated surfaces. The functionalization will be done by depositing small organic molecules in Ultra-High-Vacuum on templates with atomically controlled atomic and electronic structure.
This is achieved for instance by using vicinal Si surfaces modified by metal (like Au) submonolayer adsorbates and atomic hydrogen. Metal adatoms induce well ordered, chemically diverse nanotemplates consisting of Si terraces with variable width, embedded metal atomic rows, and Si step edge structures. This leads to chemically diverse, ordered surface structures with metallic and covalent bond character and dangling bonds, forming reactive adsorption sites for molecules. Modification by atomic hydrogen may change the surface properties significantly, an ideal base for investigating molecule-solid interactions and structure formation for inducing self- organized growth of molecular chains. We investigate such structures in-situ with complementary optical and electronic surface spectroscopy techniques, like Reflection- Anisotropy-Spectroscopy (RAS), Raman- and IR-Spectroscopy, X-Ray Photo-Electron- Spectroscopy (XPS), Low-Energy Electron Diffraction (LEED) and Scanning Tunneling Microscopy/Spectroscopy (STM/STS).
The structural info extracted from experimental spectra will be set in comparison with ab-initio calculations of atomic/molecular structure and spectral response from our cooperation partners at University Paderborn (AG Prof. Wolf-Gero-Schmidt), University of Gießen (AG Prof. Simone Sanna) and University of Rome Tor Vergata (Dr. Conor Hogan).
Our work, in cooperation with the groups of Mario Dähne and Holger Eisele focuses on nanostructured Si surfaces such as vicinal Si and metal adlayer modified surfaces. Metals like In, Au, Ag, Pb are known to induce highly ordered structures on Si. The idea is to use such atomically ordered surfaces as template for molecular structures of small organic molecules by controlling the covalent bonding to surfaces and layers. Another interest within a cooperation with the group of M. Kneissl and H. Eisele concerns wide bandgap semiconductors, like III-nitrides and III- oxides. Within GraFOx (cooperation with Holger Eisele) the surface structure and surface electronic properties will be examined using a combination of RAS, STS/STM and XPS.
Phys. Stat. Sol. (b) 255, 1700494 (2018)
Phys. Rev. Lett. 120, 166801 (2018)
Phys. Rev. B 97, 035412 (2018)
Phys. Rev. B 97, 045417 (2018)