RECORDING PERFORMANCE IN CoCrTa MEDIA WITH CoCr SEED LAYER FOR PERPENDICULAR RECORDING

Perpendicular recording disks having various magnetic properties were prepared by sputter deposition of CoCrTa storage layer with CoCr seed layer onto NiFe disks. We investigated the relation between the physical characteristics and recording properties with a low flying, single pole head. The output voltage increases linearly as the coercivity difference ( Hc⊥ - Hc〃) increases. H⊥ and Hc〃 are the perpendicular and in-plane coercivity. The overwrite is reduced as Hc⊥ increases. These results show that media with lower Hc〃, rather than with higher Hc⊥, are desirable to improve both the output and the overwrite. The noise voltage is reduced as the grain size of CoCrTa films are reduced, which might be explained by particulate media noise theory.