Spin-valve sensors with domain control hard magnet layers

Author

Kanai, H. ; Kane, J. ; Aoshima, K. ; Kanamine, M. ; Uehara, Y.

Author_Institution

Fujitsu Labs. Ltd., Atsugi, Japan

Volume

31

Issue

6

fYear

1995

fDate

11/1/1995 12:00:00 AM

Firstpage

2612

Lastpage

2614

Abstract

We have fabricated unshielded narrow-track NiFe/Cu/NiFe/FeMn spin-valve sensors with a height of 2 μm and a track-width of less than 2 μm using CoCrPt hard magnets (4πMr=5500 G, Hc=1000 Oe) as a domain control layer. Barkhausen noise was completely suppressed by a longitudinal biasing field from the CoCrPt layers. The bias state was improved by applying a strong ferromagnetic exchange coupling field of 30 Oe between the free and pinned NiFe layers through a 14 Å-thick Cu interlayer. We have also fabricated shielded CoCrPt magnet-biased spin-valve read heads with a track-width of 1.7 μm. The heads had no Barkhausen noise and very low crosstalk noise

Keywords

copper; crosstalk; ferromagnetic materials; iron alloys; magnetic domains; magnetic heads; magnetic multilayers; magnetoresistive devices; manganese alloys; nickel alloys; 2 micron; Barkhausen noise; CoCrPt; MR heads; NiFe-Cu-NiFe-FeMn; bias state; crosstalk noise; domain control hard magnet layers; longitudinal biasing field; shielded magnet-biased spin-valve read heads; spin-valve multilayers; spin-valve sensors; strong ferromagnetic exchange coupling field; trackwidth; unshielded narrow-track sensors; Anisotropic magnetoresistance; Crosstalk; Gold; Lead; Magnetic anisotropy; Magnetic domains; Magnetic heads; Magnetic multilayers; Magnetic sensors; Perpendicular magnetic anisotropy;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.490069

Filename

490069