Title :
Spinel ferrite Co-γFe2O3 perpendicular media on exchange-coupled underlayers
Author :
Koujima, Jun ; Nakata, Kenichi ; Ando, Toshio ; Shimomai, Kenichi ; Doi, Takanori ; Sugiyama, Masahiko ; Cromwell, Evan F.
Author_Institution :
R&D Div., Toda Kogyo Corp., Hiroshima, Japan
fDate :
7/1/2003 12:00:00 AM
Abstract :
Spinel ferrite Co-γFe2O3 films have the advantages of high coercivity, high stability without a protective layer, and low noise performance for magnetic recording layers. Also, exchange-coupled Co-Zr-Nb/Co-Sm underlayers show superior characteristics. The Co-Sm hard magnetic layer pins the domains of the Co-Zr-Nb soft magnetic layer effectively and decreases the noise coming from the latter. By combining the Co-γFe2O3 recording layer and exchange-coupled Co-Zr-Nb/Co-Sm underlayers, the triple-layered perpendicular media show promise for ultrahigh-density perpendicular recording.
Keywords :
Kerr magneto-optical effect; cobalt alloys; cobalt compounds; coercive force; exchange interactions (electron); ferrites; ferromagnetic materials; magnetic hysteresis; magnetic recording noise; niobium alloys; perpendicular magnetic recording; samarium alloys; zirconium alloys; Co-Sm hard magnetic layer; Co-Zr-Nb soft magnetic layer; CoFe2O3; CoZrNb-CoSm; M-H hysteresis loops; domain pinning; exchange-coupled Co-Zr-Nb/Co-Sm underlayers; exchange-coupled underlayers; high coercivity; high stability; low noise performance; magnetic recording layer; noise decrease; polar-Kerr magnetometer; spinel ferrite Co-γFe2O3 perpendicular media; triple-layered perpendicular media; ultrahigh-density perpendicular recording; Coercive force; Ferrite films; Magnetic domains; Magnetic films; Magnetic noise; Magnetic recording; Perpendicular magnetic recording; Protection; Soft magnetic materials; Stability;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2003.813774
