Title :
Spin valve films with PdPtMn antiferromagnetic layer fabricated using ultrahigh vacuum sputtering process
Author :
Shimizu, Y. ; Tanaka, A. ; Oshiki, M. ; Kataoka, Y.
Author_Institution :
Fujitsu Labs. Ltd., Atsugi, Japan
fDate :
9/1/1999 12:00:00 AM
Abstract :
We investigated the background pressure (PBG) dependence of the unidirectional anisotropy field (Hua) of spin valve films with a PdPtMn antiferromagnetic layer fabricated by an ultrahigh vacuum (UHV) sputtering process. The Hua increased with decreasing PBG until PBG reached 2×10 -7 Pa. The UHV deposition, such as below 2.0×10-7 Pa of PBG, improved the fct (111) texture of PdPtMn, the fcc(111) of NiFe/CoFeB/Cu/CoFeB layers, enlarged the grains of spin valve films, and reduced an absorption of residual oxygen component into the spin valve films. Consequently, the exchange coupled CoFeB/PdPtMn layers exhibited large Hua of 620 Oe, in spite of a quite thin PdPtMn (15 nm) as an ordered antiferromagnetic material, and the spin valve films show a large MR ratio of 7.8% and a sheet resistance change of 1.6 Ω
Keywords :
antiferromagnetic materials; giant magnetoresistance; magnetic anisotropy; magnetic thin films; manganese alloys; palladium alloys; platinum alloys; spin valves; sputtered coatings; 2E-7 Pa; PdPtMn; PdPtMn antiferromagnetic layer; background pressure dependence; exchange coupling; giant magnetoresistance ratio; grain size; residual oxygen absorption; sheet resistance; spin valve film; texture; ultrahigh vacuum sputtering; unidirectional anisotropy field; Anisotropic magnetoresistance; Antiferromagnetic materials; Argon; Giant magnetoresistance; Magnetic field measurement; Magnetic films; Mass spectroscopy; Plasma measurements; Spin valves; Sputtering;
Journal_Title :
Magnetics, IEEE Transactions on
