Title :
Magnetoresistive sensors based on Ni81Fe19/Ag multilayers
Author :
Mouchot, Jean ; Gerard, Philippe ; Rodmacq, Bernard
Author_Institution :
LETI, Grenoble, France
fDate :
11/1/1993 12:00:00 AM
Abstract :
Because of their good magnetoresistive properties and thermal stability, sputtered NiFe/Ag multilayers (MLs) produce sensors with attractive characteristics. Thermal treatments up to 280°C are carried out. They lead to improved sensitivity; the magnetoresistance (MR) ratio remains practically constant, while the saturation field decreases from 24 kA/m to 6 kA/m after annealing. Sensors are made from these MLs using a microtechnology process. They are tested by reading magnetic tracks on a hard magnetic disk. Their performance is compared with sensors based on classical anisotropic MR in ferromagnetic 3-D alloys. The signal is found to be about ten times greater with this new ML than with sensors based on NiFe or NiFeCo alloys
Keywords :
annealing; electric sensing devices; ferromagnetic properties of substances; iron alloys; magnetic multilayers; magnetic variables measurement; magnetoresistive devices; nickel alloys; silver; Ni81Fe19-Ag; Ni81Fe19/Ag multilayers; annealing; hard magnetic disk; improved sensitivity; magnetoresistance ratio; magnetoresistive sensors; microtechnology; performance; reading magnetic tracks; saturation field; sputtered multilayers; thermal stability; Magnetic anisotropy; Magnetic multilayers; Magnetic properties; Magnetic sensors; Magnetoresistance; Multilevel systems; Perpendicular magnetic anisotropy; Saturation magnetization; Sensor phenomena and characterization; Thermal stability;
Journal_Title :
Magnetics, IEEE Transactions on
