Title :
Excellent reliability of CoFe-IrMn spin valves
Author :
Iwasaki, H. ; Saito, A.T. ; Tsutai, A. ; Sahashi, M.
Author_Institution :
Res. & Dev. Center, Toshiba Corp., Kawasaki, Japan
fDate :
9/1/1997 12:00:00 AM
Abstract :
The thermal reliability of spin valve films with a CoZrNb/NiFe/CoFe free layer and a CoFe/IrMn pinned layer was investigated. Stable properties; including an MR ratio of 7.5~8%, an exchange bias of 400~500 Oe in the pinned layer, an interlayer coupling of less than 10 Oe between the pinned and free layers, and soft magnetic properties of the free layer, were observed even after annealing for 100 hours at 270°C. It was demonstrated that the IrMn/CoFe interface, as well as the CoFe/Cu interface, is extremely stable against interdiffusion. These films also showed an MR ratio of 5% and an exchange bias of 200 Oe even at 160°C
Keywords :
annealing; chemical interdiffusion; cobalt alloys; giant magnetoresistance; iridium alloys; iron alloys; magnetic heads; magnetic multilayers; magnetoresistive devices; manganese alloys; nickel alloys; niobium alloys; reliability; soft magnetic materials; zirconium alloys; 100 h; 160 to 270 degC; CoZrNb-NiFe-CoFe-Cu-CoFe-IrMn-Ta; MR ratio; annealing; exchange bias; interdiffusion; interlayer coupling; magnetic heads; pinned layer; soft magnetic properties; spin valve films; thermal reliability; Annealing; Couplings; Giant magnetoresistance; Magnetic field measurement; Magnetic films; Magnetic heads; Magnetic properties; Magnetostatics; Spin valves; Temperature;
Journal_Title :
Magnetics, IEEE Transactions on
