Sputtering of amorphous Co-Zr and Co-Hf films with soft magnetic properties

Abstract

Amorphous Co-Zr and Co-Hf films produced by sputtering have been investigated. The fundamental magnetic properties, sputtering conditions for the soft magnetic properties, and annealing to obtain high permeability films have been studied. The saturation magnetization, magnetostriction of the sputtered films, and range of composition of amorphous phase have been determined. Sensitive dependence of the soft magnetic properties on Ar gas pressure has been found. Sputtering in low Ar gas pressure suppresses the formation of microcrystals in the amorphous matrix and columnar structure in the films which deteriorates the soft magnetic properties. High permeability films have been obtained by annealing and their thermal stability was studied.