Inverted spin valves with IrMn biasing layer

Inverted IrMn-based spin valves (ISV) were fabricated with the aim of low thickness/high output dual spin valve applications. Optimized structures exhibit the following characteristics: H/sub exch/=750 Oe, R/sub sq./=18.5 /spl Omega//sq., /spl Delta/R/R=7.5% and T/sub b/=250/spl deg/C with IrMn thickness as low as 75 A. The blocking temperature distribution, however, exhibits nonzero components from 150/spl deg/C onwards. Accordingly, accelerated sheet films lifetime experiments and current heating on full read/write heads show that partial rotations of the pinned layer occur well below T/sub b/. These structures therefore appear to be insufficiently stable for disk-drive applications.