Conservation of uniaxial symmetry in Fe/Ag multilayers grown on stepped Ag(001)

We obtained a stepped Ag(0 0 1) surface by growing a 100 nm thick Ag film o n a polished MgO(0 0 1) crystal with a miscut of 1.8 in the [1 1 0] directi on. With scanning tunneling microscopy we observe terraces of (7 +/- 3) nm wide separated by mono-atomic steps that are straight over at least 200 nm in the [1 1 0] direction. The interface structure of Fe/Ag multilayers grow n at room temperature (RT) on vicinal Ag(0 0 1) is investigated for 15 mono layers (ML) of Fe and a Ag thickness ranging from 2 to 10 ML. During Fe gro wth the step structure disappears at the surface of the film. When Ag is de posited on top, steps already reappear at 2 ML. For increased Ag thickness, the steps straighten out and the roughness on terraces decreases. At 8 ML of Ag the step length and surface roughness is comparable to the uncovered Ag surface. However, on larger terraces, Ag islands are observed. In additi on we compare the direction of magnetization with respect to the surface no rmal of an [Fe(15 ML)/Ag(4 ML)], multilayer grown on vicinal and flat Ag(0 0 1). For the vicinal substrate, at RT, we observe in-plane magnetization w hereas for the flat substrate the magnetization is 29 out-of-plane. The res ults are discussed with respect to step anisotropy and step-related symmetr y. (C) 2001 Elsevier Science B.V. All rights reserved.