Abstract: Fe/Tb multilayers with various Fe layer thickness and fixed Tb layer thickness wereprepared by e-beam alternate vapor deposition. Analyses of the microstructure of thesefilms show that the magnetic performance is strongly affected by the interface struc-ture. Fe in the films evolved to amorphous phase and the Fe/Tb interface becameindiscernible with decreasing Fe thickness. At the same time, the film was observedto perform superparamagnetically, which is quite different from the ferromagnetic be-havior of Fe/Tb multilayers that have sharp Fe/Tb interface. Our work shows thatthe interface roughness has strong influence to the properties of magnetic multilayers.

Key words: magnetic multilayer, interface roughness