Regensburg 2004 – wissenschaftliches Programm
O 9.11: Vortrag
Montag, 8. März 2004, 18:15–18:30, H36
Atomic Force and Scanning Tunnelling Microscopy Measurements at Low Temperatures — •Markus Heyde, Maria Kulawik, Hans-Peter Rust, and Hans-Joachim Freund — Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany
Atomic force and scanning tunneling microscopy (AFM/STM) are the most important tools for the investigation of surfaces on the atomic scale in real space. While the STM is sensitive to the local density of states and requires a conductive surface, the AFM can be used also on insulating samples. Essential for achieving atomic resolution with an AFM is a force-detector with a low noise performance and enhanced sensitivity to short-range forces. For a detailed analysis and interpretation of surface structures, an image sensor with the capability to record AFM and STM image at the same surface area is highly desirable. A double quartz tuning fork sensor for low temperature ultra-high vacuum atomic force and scanning tunneling microscopy is presented. The features of the new sensor are discussed. In addition, a low temperature, low noise ac signal amplifier has been developed to pick-up the oscillation amplitude of the tuning fork. First atomic force measurements are shown, allowing for the resolution of different domains on a thin Al2O3 film on NiAl(110).