Tip-related artifacts in scanning tunneling potentiometry

The search for residual resistivity dipoles by scanning tunneling potentiometry

“…However, it was later pointed out by Pelz et al . [9] that such potential steps could arise from artifacts of the STP apparatus due to convolution between the tip shape and the sample topography. The origin of these types of artifacts is as follows.…”

Scanning tunneling potentiometry of semiconductor junctions

“…In addition, during the measurement the tip is scanned across the surface with the topographic feedback turned off, thereby requiring an effective means of nulling out any relative angle between the tip motion and the sample surface as well as eliminating any relative drift in their vertical positions. Finally, we note that all potentiometric measurements, if performed on rough surfaces, can suffer from significant problems of tip-sample convolution as discussed by Pelz et al [18] Concerning the above mentioned requirement for an atomically flat cleavage surface in order to apply our method, this requirement can be relaxed if a means is found to leave the usual topographic feedback on during the measurement. This can be accomplished, at least for measurements of small variations in surface potential, using the following technique.…”

The influence of surface roughness on electronic transport in thin films

“…5 therefore shows, that a rather inhomogeneous distribution of the potential on rough thin films can be expected due to the spatmlly varyipg conductances. On the other hand, the drop of the potential i~self is not as mhomogencous as found by potentiometric STM measurements on polycrystal|ine thin films [12,13], Thus, it seems to be necessary to include gram boundary scattermg in the discussion of the experimentally evaluated potential [14].…”