THESIS
2000
viii, 75 leaves : ill. ; 30 cm
Abstract
The magnetism of ultrathin magnetic film depends strongly upon the morphology and microstructure of the film. In this research project, the correlations between film morphology, magnetism and growth kinetics of Fe/Cu(l00) are studied. A strong correlation between the deposition rate and the morphology in the first two monolayers of the Fe film is discovered on the basis of low energy electron diffraction intensity oscillation measurements. At low deposition rate, the initial growth is more layer-by-layer like and at high rate the first two monolayers grow simultaneously. By monitoring the diffraction intensity oscillations and the evolution of magnetization simultaneously and continuously with spin polarized low energy electron microscopy during growth, the film thickness and the magnet...[
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The magnetism of ultrathin magnetic film depends strongly upon the morphology and microstructure of the film. In this research project, the correlations between film morphology, magnetism and growth kinetics of Fe/Cu(l00) are studied. A strong correlation between the deposition rate and the morphology in the first two monolayers of the Fe film is discovered on the basis of low energy electron diffraction intensity oscillation measurements. At low deposition rate, the initial growth is more layer-by-layer like and at high rate the first two monolayers grow simultaneously. By monitoring the diffraction intensity oscillations and the evolution of magnetization simultaneously and continuously with spin polarized low energy electron microscopy during growth, the film thickness and the magnetic transitions can be correlated with unprecedented precision. The thickness range over which the Fe film is ferromagnetic at room temperature is found to increase and the Curie temperature of the so called "live layer" phase decreases upon a reduction of the deposition rate. We argue that these magnetic phenomena occur as the result of intermixing at the interface and kinetic roughening of the surface, which are controlled by the deposition rate. A mean field growth model is used to demonstrate how intermixing may affect the initial growth morphology and possible explanations are made to account for the dependence of the magnetic transitions on the deposition rate.
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