OPTIMIZATION OF HEAD-MEDIUM PARAMETERS FOR ELECTROLESS CONIREP/NIFEP DOUBLE-LAYERED MEDIA USING RING-TYPE HEADS

Optimization of head/medium parameters for perpendicular recording on the electrolessly deposited CoNiReP/NiFeP double-layered (DL) media was examined in combination with ring-type heads. Higher reproduced voltage was obtained in the DL medium with higher underlayer coercivity, H(c)(u), (160 Oe) due to the 'phase synchronization' (PS) effect. It was necessary to adjust the perpendicular magnetization layer thickness, delta(p), in accordance with the head B(s) in order to obtain sufficient PS effect. In the higher recording density region, the combination of a small gap head (0.08 mum) and a medium with thicker delta(p) (0.3 mum) and lower H(c)(u) (50 Oe) was optimal, due to higher crystal orientation at the medium surface and improvement of head field penetration.