SELF-ASSEMBLED LATERAL MULTILAYERS FROM THIN-FILM ALLOYS OF IMMISCIBLE METALS

Thin films consisting of alloys of immiscible metals display a unique form of compositional ordering not observed in the bulk. Utilizing sca nning tunneling microscopy and low energy electron diffraction, we hav e examined thin films of CoetaAg1-eta and FeetaAg1-eta grown on Mo(110 ) surfaces. Both of these systems are observed to form a compositional ly ordered alloy of alternating, contiguous stripes of Co (or Fe) and Ag with the long axis of the stripe coinciding with the Mo[001] direct ion in the plane of the substrate. The average stripe periodicities ar e on the order of 2.0 to 2.5 nm along the Mo[<(1)over bar 10>] (perpen dicular to the stripes) direction depending on film stoichiometry.