Investigation of a metal-organic interface - realization and understanding of a molecular switch
The field of molecular organic electronics is an emerging and very dynamic area. The continued trend to miniaturisation, combined with increasing complexity and cost of production in conventional semiconductor electronics, forces companies to turn their attention to alternatives that promise the next levels of scale at significantly lower cost. After consumer electronic devices based on organic transistors, such as TVs and book readers, have already been presented, molecular electronics is expected to offer the next breakthrough in feature size. Unfortunately, most of the organic/metal interfaces contain intrinsic defects that break the homogeneity of the interface properties. In this thesis, the electronic and structural properties of such defects were examined in order to understand the influence of the inhomogeneities on the quality of the interface layer. However, the main focus of this work was the investigation of the local properties of a single molecule. Taking advantage of the Scanning Tunnelling Microscope's (STM's) ability to act as a local probe, a single molecular switch was realized and studied. Moreover, in close collaboration with theory groups, the underlying mechanism driving the switching process was identified and described. Besides the investigation of the switching process, the ability of the STM to build nanostructures of different shapes from large organic molecules was shown. Knowing the parameters for realization and control of the switching process and for building the molecular corrals, the results of this investigation enable the reconstruction of the studied molecular ensemble and its deployment in electric molecular circuits, constituting a next step towards further miniaturization of electronic devices.
info:eu-repo/classification/ddc/530, Rastertunnelmikroskop, Rastertunnelmikroskopie, Freies Molekül, Einzelmolekülspektroskopie, Switch <Kommunikationstechnik>, Physik, STM, STS, single molecule, molecular switch, vibrational heating, PTCDA
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