Growth and morphology of thin Fe films on flat and vicinal Au(111): a comparative study

Allmers T, Donath M

Research article (journal)

Abstract

The epitaxial growth of Fe on flat and vicinal Au(111) was investigated with scanning tunneling microscopy (STM) and low-energy electron diffraction (LEED) in a comparative study. Below a critical film thickness we found a pseudomorphic growth behavior of Fe on flat and vicinal Au(111). Above the critical Fe overlayer thickness a phase transition from fcc(111) to bcc(110) occurs on both surfaces. As a result of this phase transition rectangular-shaped crystallites are formed on the surface. The predominant orientation of the crystallites is along all < 01 (1) over bar >(fcc) directions for Fe on flat Au(111). For Fe on vicinal Au( 111), we observed that no crystallites are orientated along the step edges. For Fe on flat Au(111), we found that the phase transition starts at a higher Fe overlayer thickness but a lower Fe coverage is required before the transition is completed in comparison with Fe on vicinal Au(111). Our results obtained with STM and LEED allow us to directly link the growth directions of the bcc(110) crystallites with twofold symmetry to the crystallographic directions of the substrate surface with hexagonal symmetry.

Details zur Publikation

Release year: 2009
Language in which the publication is written: English