Effect of energetic bombardment on the magnetic coercivity of sputtered Pt/Co thin‐film multilayers

Pt/Co multilayers are an attractive candidate for a magneto‐optical recording medium. However, films sputter deposited in Ar have coercivities too small (100–350 Oe) to be practical in recording. By sputter depositing multilayers in Kr or Xe instead of Ar, we achieved coercivities ∼1000 Oe, suitable for recording. We attribute the lower coercivity of Ar‐sputtered films to interfacial mixing of Pt and Co layers by energetic bombardment from Ar gas atoms that recoil from the Pt target.