Title :
[Ni/Mn] superlattice-based spin-valves with high thermal stabilities
Author :
Choi, K.L. ; Kim, K.M. ; Lee, N.I. ; Kim, M.Y. ; Rhee, J.R. ; Lee, S.S. ; Hwang, D.G. ; Park, C.M.
Author_Institution :
Dept. of Phys., Sookmyung Women´´s Univ., Seoul, South Korea
fDate :
9/1/1999 12:00:00 AM
Abstract :
Ni/Mn superlattice-based spin-valve films were fabricated by dc sputtering method. Coercivity (Hc) of the pinned layer and exchange coupling field (Hex) between the pinned layer and pinning Ni/Mn superlattice with an antiferromagnetic phase were investigated in order to optimize the deposition conditions and annealing process. The thickness of each layer was controlled by deposition time. The Hex and Hc of Ni/Mn superlattice-based spin-valves increased gradually with the number of annealing cycles and number of bilayers. At the Ni composition of 38 at.% for the annealing time of 12 hours, the largest Hex and Hc of glass/[Ni/Mn]50/NiFe(60 Å)/Cu(30 Å)/NiFe(60 Å) spin-valves are 305 Oe and 245 Oe, respectively. However, the magnetoresistance (MR) ratio is small, due to the shunting effect of Ni/Mn superlattice and the interdiffusion between NiFe and Cu
Keywords :
annealing; antiferromagnetic materials; chemical interdiffusion; coercive force; copper; exchange interactions (electron); ferromagnetic materials; giant magnetoresistance; iron alloys; magnetic multilayers; manganese; nickel; nickel alloys; spin valves; sputter deposition; thermal stability; 12 h; 30 A; 60 A; Ni-Mn-NiFe-Cu-NiFe; Ni/Mn superlattice-based spin-valve films; annealing process; antiferromagnetic phase; bilayers; coercivity; dc sputtering method; deposition conditions; exchange coupling field; glass/Ni/Mn/NiFe/Cu/NiFe spin-valves; high thermal stabilities; interdiffusion; magnetoresistance ratio; pinned layer; pinning Ni/Mn superlattice; shunting effect; Annealing; Antiferromagnetic materials; Atomic layer deposition; Giant magnetoresistance; Glass; Magnetic properties; Magnetic superlattices; Physics; Sputtering; Thermal stability;
Journal_Title :
Magnetics, IEEE Transactions on
