Regensburg 2010 – scientific programme
Parts | Days | Selection | Search | Downloads | Help
HL: Fachverband Halbleiterphysik
HL 22: Graphene 2 (Joint Session with TT)
HL 22.2: Talk
Tuesday, March 23, 2010, 09:45–10:00, H21
Electrical transport and low-temperature scanning tunneling microscopy of microsoldered graphene — •Viktor Geringer1, Dinesh Subramaniam1, Ann-Kathrin Michel1, Bart Szafranek2, Daniel Schall2, Alexander Georgi1, Torge Mashoff1, Daniel Neumaier2, Marcus Liebmann1, and Markus Morgenstern1 — 1II. Physikalisches Institut, RWTH Aachen and JARA-FIT, Otto-Blumenthal-Straße, 52074 Aachen — 2Advanced Microelectronic Center Aachen (AMICA), Otto-Blumenthal-Straße 25, 52074 Aachen
Using the recently developed technique of microsoldering [1], we perform a systematic transport study of the influence of PMMA on graphene flakes revealing a doping effect of up to Δn = 3.8×1012 cm−2, but a negligible influence on mobility and gate voltage induced hysteresis. Moreover, we show that the microsoldered graphene is free of contamination and exhibits a very similar intrinsic rippling as has been found for lithographically contacted flakes. Finally, we demonstrate a current induced closing of the previously found phonon gap appearing in scanning tunneling spectroscopy experiments, strongly non-linear features at higher bias probably caused by vibrations of the flake and a B-field induced double peak attributed to the 0. Landau level of graphene.
[1] Ç. Ö. Girit and A. Zettl, Appl. Phys. Lett. 91, 193512 (2007).