Spin-valve and tunnel-valve structures with in situ in-stack bias

Author

Childress, Jeffrey R. ; Ho, Michael K. ; Fontana, Robert E. ; Carey, Matthew J. ; Rice, Philip M. ; Gurney, Bruce A. ; Tsang, Ching H.

Author_Institution

IBM Almaden Res. Center, San Jose, CA, USA

Volume

38

Issue

5

fYear

2002

fDate

9/1/2002 12:00:00 AM

Firstpage

2286

Lastpage

2288

Abstract

The use of in-stack longitudinal magnetic stabilization for spin-valve and tunnel-valve recording head sensors has been investigated. An in-stack ferromagnetic layer pinned with an IrMn antiferromagnet is used to magnetostatically stabilize the free layer by flux closure. The use of IrMn with lower blocking temperature than PtMn allows the bias layer to be set independently from the PtMn-pinned reference layer in the spin-valve or tunnel-valve. A Ta spacer 10-30 Å in thickness is used to separate the free layer from the bias layer resulting in low coupling fields. IrMn delivers up to 0.34 erg/cm² of pinning strength, resulting in stable unshielded sensor operation for device sizes below 0.2 μm.

Keywords

magnetic heads; magnetoresistive devices; spin valves; tunnelling; IrMn; IrMn antiferromagnet; PtMn; PtMn antiferromagnet; Ta; Ta spacer; blocking temperature; coupling field; ferromagnetic layer; flux closure; in situ in-stack bias; longitudinal magnetostatic stabilization; magnetoresistive device; pinning strength; recording head sensor; spin-valve structure; tunnel-valve structure; Insulation life; Magnetic flux; Magnetic heads; Magnetic recording; Magnetic sensors; Magnetic separation; Magnetosphere; Magnetostatics; Perpendicular magnetic recording; Stability;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/TMAG.2002.802802

Filename

1042163