Faculty of Engineering and Natural Sciences
Simultaneous Atomic Force/Scanning Tunneling Microscopy and its applications
H. Özgür Özer
We studied TiO2(110) surface with AFM/STM operating with very small oscillation amplitudes. Topography, force gradient, barrier height, and dissipation are measured simultaneously using sub-angstrom oscillation amplitudes. Both home-made W and commercial Si levers were used in the experiments. STM topography and force gradient scans exhibited contrast inversions due to tip or experimental parameter changes. We obtained all combinations of sign of contrast between STM and force gradient with both W and Si tips. The inversions in STM and force gradient contrast were usually not correlated to each other. Interestingly, one type of STM contrast, which seems to have not been pronounced much in the literature, occurs in almost half of the scans with either W or Si tips. The experimental results will be introduced with some empirical analysis of images along with force-distance spectroscopy.
December 2, 2009, 13:40,FENS L045