Title :
Thickness and oxidation dependence of magnetic properties of ultrathin obliquely evaporated Co-CoO media
Author :
Motohashi, Kazunari ; Onodera, Seiichi
Author_Institution :
Recording Media Co., Sony Corp., Miyagi, Japan
Abstract :
Magnetic properties of ultrathin obliquely evaporated Co-CoO media particularly targeted for a helical scanning tape system using high-sensitivity giant magnetoresistive heads were investigated. By introducing oxygen, decoupling of magnetostatic interaction between ferromagnetic particles led to a maximum value of coercivity at a certain oxygen amount. Coercivity was also sharply deteriorated by decreasing the magnetic layer thickness. Analysis of magnetic torque measurement revealed that obliquely evaporated Co-CoO media has an initial growth layer with a thickness of 10.2 nm. Application of a SiO2 underlayer is effective in preventing the deterioration of coercivity for thin magnetic media design.
Keywords :
cobalt; cobalt compounds; coercive force; magnetic heads; magnetic particles; magnetic recording; magnetic tapes; magnetic thin films; magnetoresistive devices; oxidation; vacuum deposited coatings; 10.2 nm; Co-CoO; coercivity; ferromagnetic particles; helical scanning tape system; high-sensitivity giant magnetoresistive heads; magnetic layer thickness; magnetic properties; magnetic torque measurement; magnetostatic interaction; oxidation dependence; thickness dependence; thin magnetic media design; ultrathin obliquely evaporated Co-CoO media; Coercive force; Giant magnetoresistance; Magnetic anisotropy; Magnetic flux; Magnetic properties; Magnetostatics; Oxidation; Perpendicular magnetic anisotropy; Perpendicular magnetic recording; Saturation magnetization;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2003.816294
