Atom Manipulation With The STM: Nanostructuring And Femtochemistry

One possible future way to create new materials and devices consists in the atom by atom assembling of functional structures on solid substrates. The instrument with which manipulations on atomic scale became possible is the scanning tunneling microscope [ I , 21. The two basic modes of the transport of atoms or molecules to form proper patterns consist of picking up the particles with the tip and releasing them back to the surface at the desired places (vertical manipulation) or to move them along the surface maintaining contact to the substrate (lateral manipulation). For a secure control of both transfer modes the basic physical steps, involved in both manipulation modes have to be known.