Development of Co-alloys for perpendicular magnetic recording media

Author

Lu, Bin ; Weller, Dieter ; Ju, Ganping ; Sunder, Ashwin ; Karns, Duane ; Wu, Meiling ; Wu, Xiaowei

Author_Institution

Seagate Technol., Pittsburgh, PA, USA

Volume

39

Issue

4

fYear

2003

fDate

7/1/2003 12:00:00 AM

Firstpage

1908

Lastpage

1913

Abstract

Exploring new Co-alloy compositions to achieve both chemical segregation and suitable magnetic properties is a priority task for the development of future perpendicular magnetic recording media. With proper interlayer (IL) design, columnar Co-alloy grains with narrow orientation distribution (Δθ₅₀< 6°) have been obtained on thin ILs (4 nm thick). We demonstrate CoCrPtB-alloys with full remanence squareness and large negative reverse field (H_r<-1.5 kOe) at low IL and magnetic layer thickness of 4 and 11 nm, respectively. It is also shown that carbon overcoat thickness reduction results in a signal-to-noise ratio gain of about 0.5 dB/nm.

Keywords

boron alloys; chromium alloys; cobalt alloys; coercive force; ferromagnetic materials; grain size; magnetic recording noise; magnetic thin films; perpendicular magnetic recording; platinum alloys; remanence; sputtered coatings; 11 nm; 4 nm; C; Co-alloy composition; CoCrPtB; CoCrPtB-alloys; carbon overcoat thickness reduction; chemical segregation; coercivity; columnar Co-alloy grains; full remanence squareness; interlayer design; large negative reverse field; magnetic layer thickness; magnetic properties; narrow orientation distribution; perpendicular magnetic recording media; signal-to-noise ratio gain; sputter deposited media; Anisotropic magnetoresistance; Chemicals; Crystallography; Grain size; Magnetic anisotropy; Magnetic flux; Magnetic separation; Microstructure; Perpendicular magnetic recording; Soft magnetic materials;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/TMAG.2003.813779

Filename

1211157