Growth and magnetic properties of Fe films on InP(001)

Abstract

An investigation of the InP(001) surface and the characterization of thin Fe films grown on this substrate at $\ensuremath{\approx}150$ and $\ensuremath{\approx}300 \mathrm{K}$ are presented. As substrates, highly ordered P-rich $(2\ifmmode\times\else\texttimes\fi{}4)$ reconstructed surfaces obtained by ${\mathrm{Ar}}^{+}$ ion bombardment at $\ensuremath{\approx}570 \mathrm{K}$ were used. The growth of Fe films in the submonolayer thickness range and the magnetic properties of thin Fe films grown on P-rich $(2\ifmmode\times\else\texttimes\fi{}4)$ InP(001) are reported. We observe a uniaxial in-plane magnetic anisotropy up to an Fe thickness of $\ensuremath{\approx}14$ monolayers, which is related to the uniaxial character of the InP(001) reconstruction. From the magnetization behavior we obtained the surface/interface contribution to the uniaxial anisotropy, and deduced that very small, if any, magnetically dead layers form at the interface. Auger electron spectroscopy data reveal that about one monolayer of In segregates to the top of the growing Fe film at $\ensuremath{\approx}300 \mathrm{K},$ but does not support a strong Fe-InP(001) intermixing, in contrast to the current belief. The current-voltage characterization of patterned Fe films grown on n-InP(001) shows nonrectifying contacts at room temperature.