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

Volume

39

Issue

5

fYear

2003

Firstpage

2350

Lastpage

2352

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;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/TMAG.2003.816294

Filename

1233073