Regensburg 2019 – wissenschaftliches Programm

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O: Fachverband Oberflächenphysik

O 66: Poster Wednesday: 2D Materials

O 66.14: Poster

Mittwoch, 3. April 2019, 17:45–20:00, Poster B2

Sample preparation for Graphene Enhanced Raman Spectroscopy — •Stephan Sleziona, Simon Rauls, Leonard Christen, Tobias Foller und Marika Schleberger — Universität Duisburg-Essen, AG Schleberger, Germany

Graphene-enhanced Raman spectroscopy (GERS) has been shown to be a powerful tool for ultrasensitive detection of adsorbed molecules [1]. As a possible mechanism charge transfer is often suggested, which depends on the Fermi-level of the graphene, the HOMO-LUMO levels of the molecules and the excitation laser energy [2, 3]. Therefore, a combination of changing the fermi level in a graphene-based field effect device (GFET) and the excitation laser energy allows to investigate the coupling of this hybrid system. We prepared GFETs in two different ways: (i) with graphene grown by chemical vapor deposition (CVD) using photolithography and (ii) with exfoliated graphene using electron beam lithography (EBL). Cobalt Octaethylporphyrin (CoOEP) is deposited via thermal evaporation onto our substrates and the growth is analyzed using Raman spectroscopy and atomic force microscopy. Furthermore, we compare these fully processed samples with pristine samples to study possible influences of our lithography process on the various properties, such as graphene quality, molecular adsorption, and changes in the charge transfer mechanism of GERS.

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