title: Diffusional kinetics of SiGe dimers on Si(100) using atom-tracking scanning tunneling microscopy
abstract: Quantitative measurements of the diffusion of adsorbed mixed Ge-Si dimers on the Si(100) surface have been made as a function of temperature using atom-tracking scanning tunneling microscopy. These mixed dimers are distinguishable from pure Si-Si dimers by their characteristic kinetics-a 180 degrees rotation between two highly buckled configurations. At temperatures at which the mixed dimers diffuse, atomic-exchange events occur, in which the Ge atom in the adsorbed dimer exchanges with a substrate Si atom. Reexchange can also occur when the diffusing Si-Si dimer revisits the original site of exchange.
authors.affiliation: University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
authors.initials: XR
authors.lastname: Qin
authors.initials: BS
authors.lastname: Swartzentruber
authors.initials: MG
authors.lastname: Lagally