Influence of Rippled Substrate Morphology on the Interlayer Exchange Coupling in Fe/Cr/Fe Thin Films

We have investigated the interlayer exchange coupling in Fe (4nm)/Cr (x nm)/Fe (4nm) thin film trilayers (x=0–5 nm) deposited on rippled armorphous silicon substrates. The substrate surface was periodically modulated (periods of 20 nm, 35 nm, and 50 nm) by Ar+ ion erosion. The influence of the resulting surface and interface structure on the magnetic properties has been investigated by magneto-optical Kerr effect (MOKE). We found an orange peel type coupling, predicted by Néel’s theory and, due to the morphology of the magnetic layers, a strong uniaxial magnetic anisotropy in the system.
This work is supported by DFG grant FA 314/6-1.