Magnetic properties of crystalline and amorphous Co-Zr, Nb, Mo thin film alloys

Abstract

This paper reports the results of measurements of some magnetic properties of Co-Zr, Co-Nb and Co-Mo thin film alloys prepared at cobalt concentrations between 100 and 65 at.%. The films were produced by sputter deposition in a DC triode system. The alloys are found to be amorphous above critical concentrations of the non-magnetic transition metal. The room temperature saturation magnetisation decreases monotonically from a value near to that of bulk cobalt to zero at a cobalt concentration of about 70 at.%. Films of the first two alloy series are characterised by in-plane magnetisation in both the crystalline and amorphous phases, whereas crystalline Co-Mo films can exhibit perpendicular magnetisation as observed in Co-Cr alloy films.