Exchange coupling and GMR properties in ion beam sputtered hematite spin-valves

Author

Sano, M. ; Araki, S. ; Ohta, M. ; Noguchi, K. ; Morita, H. ; Matsuzaki, M.

Author_Institution

Data Storage Components Bus. Group, TDK Corp., Nagano, Japan

Volume

34

Issue

2

fYear

1998

fDate

3/1/1998 12:00:00 AM

Firstpage

372

Lastpage

374

Abstract

We have succeeded in fabricating hematite (α-Fe₂O ₃) antiferromagnetic (AF) thin films by the ion beam sputtering method, which give unidirectional anisotropy to the adjacent ferromagnetic layer. Its exchange bias energy (J_ex) is 0.03 erg/cm², and blocking temperature (T_b) is 250°C. Spin-valve films with the hematite AF layer were also fabricated. They exhibit GMR property with unidirectional anisotropy of the pinned layer. Spin- valve films of which magnetic layers consist of only NiFe exhibit relatively low MR ratio and poor thermal stability. However, the spin-valve using Co as the pinned layer and the free layer at the Cu interface exhibits MR ratio of more than 6% and excellent thermal stability

Keywords

antiferromagnetic materials; exchange interactions (electron); giant magnetoresistance; ion beam applications; magnetic anisotropy; magnetic heads; magnetic thin films; magnetoresistive devices; spin waves; sputter deposition; 250 degC; Fe₂O₃; GMR properties; GMR property; MR heads; MR ratio; antiferromagnetic thin films; blocking temperature; exchange bias energy; exchange coupling; hematite spin-valves; ion beam sputtering; pinned layer; spin-valve films; thermal stability; unidirectional anisotropy; Anisotropic magnetoresistance; Antiferromagnetic materials; Ion beams; Magnetic anisotropy; Magnetic films; Optical coupling; Sputtering; Temperature; Thermal stability; Valves;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.667766

Filename

667766