Sputtered NiFeZr as a soft biasing layer in MR head

Abstract

The sputtered soft magnetic NiFeZr films were studied experimentally for the use as a soft adjacent layer (SAL) in magnetoresistive (MR) heads. The influence of the film thickness and sputtering conditions on the magnetic and electrical properties of the films was investigated. The coercivity H/sub C/ and the anisotropy field H/sub K/ considerably depends on the substrate temperature T/sub S/ during the deposition. The films of the thickness below 400 /spl Aring/ have the following properties: H/sub C/<0.5 Oe, H/sub K/<6 Oe, a resistivity /spl rho/=91 /spl mu/Ohm/spl middot/cm, a magnetoresistance ratio /spl Delta//spl rho///spl rho/<0.05%, a saturation induction B/sub s/=0.65 T, and a magnetostriction constant /spl lambda//sub s/=4/spl times/10/sup -7/. The films exhibit stable amorphous structure. The above results show that sputtered NiFeZr films emerge as a good candidate for SAL in MR heads. Some characteristics of three-layered (NiFeZr/Ta/NiFe) MR elements have also been discussed in this paper.