Formation of ultrathin iron magnetic films on the silicon vicinal surface

Abstract

The phase composition, electronic structure, and magnetic properties of ultrathin layers of iron and iron silicides formed upon deposition of 1- to 25-A-thick Fe film on an atomically clean vicinal surface Si(100) at room temperature have been investigated using high-resolution photoelectron spectroscopy with synchrotron radiation and the magnetic linear dichroism in Fe 3p electron photoemission. It has been demonstrated that the phases involved (Fe-Si solid solution, the Fe3Si silicide, the iron film) are formed in the same order as in iron deposition on the Si(100) singular face; in this particular case, the segregation of silicon on the iron film is noticeably enhanced. It has been established that the ferromagnetic ordering of the films in the plane of the sample surface follows a threshold character and sets in after a 7-A-thick film has been deposited during the stage of growth of the Fe3Si silicide. A further deposition brings about an increase in the remanent magnetization of the film, which reaches saturation at coverages of about 20 — ricated exhibits magnetic anisotropy with the easy magnetization axis aligned with the substrate steps.