Study of the growth of Fe on Ru(0001) by low-energy electron diffraction

Abstract

Qualitative and quantitative LEED (low-energy electron diffraction) and AES (Auger electron spectroscopy) studies of the growth of Fe films on Ru(0001) show that the growth mode is the Stranski-Krastanov mode: monolayer growth followed by island growth. The first monolayer of Fe is pseudomorphic with the hexagonal Ru(0001) net at an interlayer spacing of 2.05 Å: the Fe atoms are in the sites dictated by continuation of the substrate's hexagonal close-packed (hcp) stacking. Thicker films consists of 3-dimensional bcc- Fe{ 100} domains in two equivalent Kurdjumov-Sachs orientations, rotationally related to one another by the 6-fold symmetry of the substrate net. These results do not support recent reports of the growth of hcp Fe on Ru(0001). Possible connections between the present structure results and the magnetic properties of Fe/Ru ultra-thin films reported by others are discussed. © 1991.