Effects of sputter gas medium on the nanometer-scale surface structures of the Pt/Co multilayers

The surface structure of polycrystalline Pt/Co multilayer thin films, sputter-deposited on glass substrates with Ar, Kr, or Xe, was obtained with near-atom resolution by scanning tunneling microscopy. Monatomic steps separating narrow terraces on the Ar-sputtered films and large step-like structures on the order of the Pt/Co bilayer thickness on the Xe-sputtered films were observed. We attributed differences in surface features to bombardment of the growing film surface by reflected neutral inert gas atoms with different energy distributions. We correlated the observed surface structures with magnetic coercivity of these films.