Title :
Unshielded spin-valve sensors exchange-biased by thin TbCo layers
Author :
Leal, J.L. ; Oliveira, N.J. ; Rodrigues, Leonardo Martins ; Sousa, A.T. ; Freitas, P.P.
Author_Institution :
INESC, Lisbon, Portugal
fDate :
11/1/1994 12:00:00 AM
Abstract :
Unshielded spin-valve sensors were fabricated with trackwidth W varying from 25 to 2 micron and height h ranging from 7 to 1 micron. Magnetoresistance signals range from 7.5% to 3%. We find that heads with a geometry W/h⩾4 are Barkhausen noise free. The effect of current density on sensor heating and output linearization is described. The pinned NiFe layer is exchange-biased to a 120 Å thick TbCo layer, where the exchange field can be tuned by changing the TbCo thickness
Keywords :
Barkhausen effect; cobalt alloys; iron alloys; magnetic heads; magnetic multilayers; magnetoresistance; magnetoresistive devices; nickel alloys; terbium alloys; 1 to 7 micron; 2 to 25 micron; Barkhausen noise; NiFe-TbCo; current density; exchange biasing; exchange field; magnetic heads; magnetoresistance signals; output linearization; sensor heating; trackwidth; unshielded spin-valve sensors; Current density; Geometry; Hysteresis; Magnetic heads; Magnetic sensors; Magnetoresistance; Sensor phenomena and characterization; Sputter etching; Substrates; Thermal sensors;
Journal_Title :
Magnetics, IEEE Transactions on
