摘要 |
A hard bias structure for biasing a free layer in a MR element within a magnetic read head is comprised of a soft magnetic underlayer such as NiFe and a hard bias layer comprised of Co<SUB>78.6</SUB>Cr<SUB>5.2</SUB>Pt<SUB>16.2 </SUB>or Co<SUB>65</SUB>Cr<SUB>15</SUB>Pt<SUB>20 </SUB>that are rigidly exchange coupled to ensure a well aligned longitudinal biasing direction with minimal dispersions. The hard bias structure is formed on a BCC seed layer such as CrTi to improve lattice matching. The hard bias structure may be laminated in which each of the underlayers and hard bias layers has a thickness that is adjusted to optimize the total H<SUB>C</SUB>, M<SUB>r</SUB>t, and S values. The present invention encompasses CIP and CPP spin values, MTJ devices, and multi-layer sensors. A larger process window for fabricating the hard bias structure is realized and lower asymmetry output and NBLW reject rates during a read operation are achieved.
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