Title :
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
fDate :
3/1/1998 12:00:00 AM
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 (Jex) is 0.03 erg/cm2, and blocking temperature (Tb) 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;
Journal_Title :
Magnetics, IEEE Transactions on
