Audit hochschule und familie
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Position Indication:
Content
2015 - Ebrahim Ghanbari
Growth of organic thin films
Conference participation and research stay at ..., San Antonio, TX, USA
01/03/2015 - 31/03/2015
Ebrahim Ghanbari
Contact: vorname.nachname(/\t)jku.at
I am a PhD student under the supervision of Thorsten Wagner in the AOP team at the Institute of Experimental Physics. My research focuses on the correlation of the optical and electronic properties of organic nano-structures at the microscopic scale. In order to characterize the interface between an organic layer and its substrate, many studies have addressed the growth of thin films of organic molecules on metal substrates, using snapshots obtained while the deposition of the organic thin film was interrupted. Our group at JKU pioneered in implementing an in-situ combination of optical spectroscopy and photoemission electron microscopy (PEEM) to follow the growth of α-sexithiophene (α-6T) on Ag (111) surfaces in real time.
Both, the control of the orientation of the molecular stacking, as well as the precise understanding as well as control of thin-film growth are crucial. A specific aim of my investigations is to systematically compare the geometric ordering of chemically different but geometrically similar molecules on the same surface. We consider here metal substrates, because these can provide strong surface-adsorbate interactions with the molecule, in an interplay with substantial adsorbate-adsorbate interactions. With our method the optical spectra as well as the surface topography can now be accomplished from a single sample, layer by layer. In this way information about properties such as molecular orientation, lateral order and electronic structure can be combined in order to arrive at a detailed and consistent understanding.
I presented the results we achieved so far in an oral presentation entitled “Layer resolved evolution of α-sexithiophene films: Correlation between PEEM and optical reflectance” at the APS March 2015 meeting. In addition to acquiring expertise on specific experimental challenges and data analysis in Linz, my participation in this conference and the critical discussion of various aspects of my research with collegues forms an important part of my PhD work. It was a unique opportunity to further develop my knowledge on PEEM and optical reflectance techniques.