FMR STUDIES OF MAGNETIC-PROPERTIES OF CO AND FE THIN-FILMS ON AL2O3 AND MGO SUBSTRATES

The effect of substrates on the magnetic properties has been studied f or Co and Fe films both on Al2O3 (11 $$($) over bar 20) and MgO (001) substrates by using ferromagnetic resonance techniques. For Fe(001)/ M gO(001) samples the thickness dependence of the magnetocrystalline con stant and of the effective magnetization values have been determined f rom the in-plane angular variation of the resonance field H-O. Differe nt reasons for the thickness dependencies of these parameters are disc ussed. For Co(111)/Al2O3(11 $$($) over bar 20) the angular variation o f H-O exhibits an uniaxial anisotropy, for which several causes are di scussed. For Co(11 $$($) over bar 20)/MgO(100) a four-fold in-plane an isotropy was observed which is due to the twinned structure of these s amples.