Epitaxial magnetic Fe layers grown on Si(001) by means of a template method

We demonstrate the possibility of growing good-quality epitaxial Fe films o n a Si(001) substrate, opening up new prospects to prepare ferromagnetic su perlattices on this substrate. A template technique prevents the formation of disordered interfacial iron silicides. Transmission electron microscopy reveals that the Fe layers are fairly uniform in thickness with abrupt inte rfaces and in majority epitaxial relationship Fe(001)[100]//Si(001)[100]. B oth the diffraction data and the observation of Moire fringes indicate that the Fe lattice is almost relaxed towards its bulk bcc phase in thick layer s [greater than or equal to 40 monolayers (ML)] but is still strained by th e substrate in the thinnest films. Magneto-optical Kerr effect measurements show that the films evaporated at normal incidence with a thickness above 4 ML are ferromagnetic at room temperature and exhibit in-plane biaxial ani sotropy. (C) 2000 Elsevier Science B.V. All rights reserved.