Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

O: Fachverband Oberflächenphysik

O 73: Scanning Probe Methods II

O 73.3: Vortrag

Donnerstag, 3. April 2014, 11:00–11:15, WIL A317

Dynamic local work function measurement and the role of topography — •Ferdinand Huber¹, Sonia Matencio², Alfred J. Weymouth¹, and Franz J. Giessibl¹ — ¹Institute for Experimental and Applied Physics, University of Regensburg, 93040 Regensburg, Germany — ²Institute of Material Science of Barcelona (ICMAB-CSIC), Campus UAB, 08193 Bellaterra, Spain

Performing simultaneous STM/AFM allows the electronic structure of the surface to be investigated. Two common methods are Kelvin Probe Force Microscopy (KPFM) and current-distance (I-z) spectroscopy. With KPFM, the tunneling current channel is difficult to interpret because the applied bias is not constant. I-z spectroscopy is usually performed at low temperature in order to minimize drift and creep. We propose an alternate technique called dynamic κ measurement based on Refs. [1] and [2], in which we measure the decay constant of the tunneling current taking advantage of the oscillating conducting tip. We explain this technique and compare it to measurements at low temperature. Furthermore we discuss the influence of topography on the local work function.

[1] G. Binnig, H. Rohrer, Surf. Sci. 126, 236 (1983)

[2] M. Herz, Ch. Schiller, F. Giessibl and J. Mannhart, Appl. Phys. Lett. 86, 153101 (2005)