Patent ID: 6995961

Claim:
A magnetic sensing element having a multilayer comprising a first antiferromagnetic layer, a pinned magnetic layer, a nonmagnetic material layer and a free magnetic layer laminated in this order, a pair of second antiferromagnetic layers formed with a distance therebetween in a track width direction so as to be stacked at least on both side regions of the free magnetic layer in the track width direction, said free magnetic layer including at least one of a Ni a Fe b layer, a NiFeX layer, an amorphous Co alloy layer containing an amorphous Co based magnetic material, and a CoFeX layer, wherein a and b in Ni a Fe b represented by at % satisfy the relation of a>80 with a+b=100, wherein X in the NiFeX layer represents at least one element selected from Mn, Cu, Zn, Ti, Al, Ge, Si, Cr, V, Sn, Ir, Ru, Nb, Sb, W, Mo, Os and Ta, wherein X in the CoFeX layer represents at least one element selected from Ti, Al, Mn, Si, V, Cr, Ta, Zn, Sb, Ge, Mo and W, wherein the free magnetic layer comprises a (Co x Fe y ) e Cr f layer as one of an uppermost layer and lowermost layer closest to the second antiferromagnetic layer, x and y are represented by an at % ratio of Co to Fe satisfying the relation of x+y=1, and e and f are represented by at % satisfying the relations of 0<f<20 and e+f=100.