Berlin 2008 – wissenschaftliches Programm

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O: Fachverband Oberflächenphysik

O 77: Methods: Scanning Probe Techniques I

O 77.1: Vortrag

Donnerstag, 28. Februar 2008, 15:30–15:45, MA 041

Advanced Spherical Probes for Atomic Force Microscopy — •Jan-Erik Schmutz, Marcus M. Schäfer, and Hendrik Hölscher — CeNTech, Universität Münster, Heisenbergstr. 11, 48149 Münster, Germany

In some areas of scanning probe microscopy it is highly important to use tips with a well defined radius [1]. This problem is commonly solved by glueing a microsphere onto the end of a tipless cantilever [2]. Though this technique is widely used we found some drawbacks especially for spheres with a radius smaller than 5 µm. Both in friction force microscopy (FFM) and in dynamic force microscopy (DFM) the effective tip height is an important parameter. In FFM the torsional spring constant is inversely propotional to the square of the tip height. Therefore, increasing the tip height decreases the torsional spring constant which leads to an enhanced sensitivity. Moreover with an increased tip height the risk of the cantilever edge touching a rough surface is being reduced. The main problem in DFM with a small tip height is the increased damping due to the compressed air in the gap between the cantilever and the surface [3]. Here we present a new cantilever design which avoids these disadvantages.
W. A. Ducker et al., Nature 353, 239 (1991)
L. H. Mak et al., Rev. Sci. Instrum. 77, 046104 (2006)
O. I. Vinogradova et al., Rev. Sci. Instrum. 72, 2330 (2001)