|
The self-organisation of molecules on surfaces promises a path towards functional nanostructures that may be used for nanodevices, optoelectronics or chemical sensors. Recent interest has been sparked in particular in the use of carboxylic acid groups for creating supramolecular structures. To understand the reactions involved on a nanometer length scale, it is important to see in a fundamental study how the molecule arranges on the surface and what interactions it undergoes. In this present work, the growth of an organic layer of TMA was studied in ultra-high vacuum by depositing it on metallic and semi-conducting surfaces. The deposition of TMA layers on Cu(110) results in two different superstructures having (5x3) periodicity for low coverages and (4x4) periodicity for a saturated monolayer coverage. The detailed bond configuration of the molecule on the surface can be determined using X-ray photoelectron spectroscopy (XPS). Analysis of chemical shifts reveals that molecular linking is provided by a dehydrogenation of the carboxylic groups, which are then connected via the oxygen atoms to the Cu substrate. This leads to ordered metal-organic chains. Detailed results for TMA films on Cu(110) and preliminary findings for TMA films on SiC surfaces will be presented and discussed. |