Overall the magnetic properties of the Fe/Si multilayers made by IBS are similar to those made previously by magnetron sputtering.[5,25] Definitive confirmation of AF interlayer coupling in our multilayers has been obtained by polarized neutron reflectivity measurements. For some unknown reason the magnetic properties of our multilayers are closer to those of the magnetron-sputtered multilayers than those reported on in a previous study using IBS, where much lower saturation fields were observed. The differences between the previous IBS-grown films and ours may be related to the lower ion-beam voltage used by Inomata et al. Comparisons on the basis of layer thickness are made here only between films grown during the same deposition run in order to insure that the relative layer thicknesses are meaningful. Films with similar layer thicknesses have been grown many times to establish reproducibility of the observed trends.