TU Berlin

Arbeitsgruppe Prof. Dr. M. DähneScanning-tunneling microscopy (STM)

Inhalt des Dokuments

zur Navigation

Scanning tunneling microscopy (STM)


The Scanning Tunneling Microscope (STM), developed in the 80's, allows imaging of surface topographies down to atomic resolution. In an STM, a sharp metallic tip is positioned very close (a few Å) away from the surface under study, so that a tunneling current flows between tip and surface when a voltage is applied. Because of the strong (exponential) variation of the tunneling current with the distance, the latter can be controlled by keeping the tunneling current at a constant value using a feedback loop. For imaging, the tip is scanned across the surface, while the tip height is measured as a function of lateral position. The data from these line scans are usually converted to a grey-shade image, with the higher tip positions appearing with brighter color.



Schnellnavigation zur Seite über Nummerneingabe