PERPENDICULAR MAGNETIC RECORDING DISK WITH MULTIPLE MAGNETIC LAYERS AND INTERMEDIATE DUAL NUCLEATION FILMS FOR CONTROL OF GRAIN SIZE

摘要

PROBLEM TO BE SOLVED: To provide a perpendicular magnetic recording disk with multiple magnetic layers and intermediate dual nucleation films for control of grain size.;SOLUTION: A perpendicular magnetic recording disk has a graded-anisotropy recording layer (RL) formed of at least two ferromagnetically exchange coupled CoPtCr-oxide magnetic layers (MAG1 and MAG2) with two nucleation films (NF1 and NF2) between the magnetic layers. NF1 is a metal film, preferably Ru or a Ru-based alloy like RuCr. NF2 is a metal oxide film, preferably an oxide of Ta, deposited on NF1 at a thickness of about 0.2-1.0 nm. MAG2 is deposited on NF2. NF1 and NF2 provide a significant reduction in average grain size in the RL from a graded-anisotropy RL without nucleation films between MAG1 and MAG2, while also assuring that MAG1 and MAG2 are strongly exchange coupled.;COPYRIGHT: (C)2013,JPO&INPIT