Annealing effect on spin-valve sensor transfer curves

Author

Redon, Olivier ; Albuquerque, Gonçalo B. ; Rodrigues, Luis M. ; Silva, Fernando I. ; Freitas, Paulo P.

Author_Institution

Silmag, St Egreve, France

Volume

34

Issue

2

fYear

1998

fDate

3/1/1998 12:00:00 AM

Firstpage

562

Lastpage

567

Abstract

Unshielded spin-valve sensors were fabricated and annealed to study the effect of high temperature processing on the transfer curves. A micromagnetic simulation program was developed to analyze the changes observed on the transfer curves upon annealing. Analysis of experimental data versus the micromagnetic simulations indicates two causes responsible for the progressive loss of the MR signal upon annealing above the blocking temperature: a rotation of the pinned layer magnetization from the transverse to the longitudinal direction (along the sensor trackwidth) and an increase of the free layer anisotropy. Rotation of the free layer easy axis can also be observed. Cool down in a magnetic field can prevent this MR loss by pinning the magnetization direction during the high temperature stage

Keywords

annealing; magnetic anisotropy; magnetic heads; magnetic sensors; magnetoresistive devices; annealing; blocking temperature; easy axis; free layer anisotropy; high temperature processing; magnetoresistive head; micromagnetic simulation; pinned layer magnetization rotation; spin-valve sensor; transfer curve; Analytical models; Anisotropic magnetoresistance; Data analysis; Magnetic analysis; Magnetic sensors; Magnetization; Micromagnetics; Signal analysis; Simulated annealing; Temperature sensors;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.661492

Filename

661492