Leed measurements of Fe epitaxially grown on Cu(100)

Abstract

Iron was epitaxially grown on a Cu(100) surface. Low energy electron diffraction (LEED) intensity versus energy curves were recorded for 1 and 10 layers of iron on Cu(100) at room temperature. A full dynamical analysis was performed using the renormalized forward scattering perturbation method. The surface Debye temperatures were determined to be 233 K for 1 ML Fe and 380 K for 10 layers of Fe. The value obtained for fcc iron was 550 K. A multiple relaxation approach was employed in analyzing the experimental data. The estimated interlayer spacings for the first and second layers were 1.78±0.02 Å (first) and 1.81±0.02 Å (second) for 1 ML Fe, and 1.81±0.02 Å (first) and 1.78±0.02 Å (second) for 10 layers of Fe on Cu(100). Auger electron spectroscopy was used to determine the thickness of the Fe films, and the LEED measurements indicate approximately a layer-by-layer growth until about 17 layers at room temperature. At higher temperatures there is evidence of iron diffusion or copper surface segregation.