Roos, Kelly Ryan; Roos, Kimberly L.; Lohmar, I.; Wall, Dirk; Krug, J.; Horn-von Hoegen, Michael; Meyer zu Heringdorf, Frank:

Real-Time View of Mesoscopic Surface Diffusion

In: Physical Review Letters, Jg. 100 (2008), S. 16103 (4p)
ISSN: 0031-9007, 1079-7114
Zeitschriftenaufsatz / Fach: Physik
Fakultät für Physik » Experimentalphysik
Photoemission electron microscopy is used to study the thermal decay of Ag islands grown epitaxially on Si(001) surfaces. (2×3) Ag reconstructed zones, due to migrating Ag atoms supplied to the surface by the decaying islands, surround each of the islands. The shape of these reconstructed zones depends on the degree of diffusion isotropy in the system. We demonstrate that the imaging of these reconstructed “isocoverage zones” constitutes a unique experimental method for directly observing diffusion fields in epitaxial systems. We describe the dynamics of the thermal decay of the islands and the isozones in the context of a continuum diffusion model