Magnetic tunnel junction magnetoresistive read head with a sensing layer as a flux guide

摘要

PROBLEM TO BE SOLVED: To provide an MTJ(magnetic tunnel junction) MR(magneto-resistance) read head free from problems accompanying the existence of an edge part of an exposed MTJ layer on a detection surface. ;SOLUTION: The MTJ magneto-resistance read head for magnetic recording system is provided with an MTJ detection or free ferromagnetic layer 132 functioning as a magnetic flux guide which directs a magnetic flux from a magnetic recording medium to a tunnel junction. An MTJ fixed ferromagnetic layer 118 has a front edge part retreated from the detection surface of the head. The fixed ferromagnetic layer and the free ferromagnetic layer are brought into contact with opposite faces of an MTJ tunnel barrier layer 120, but the free ferromagnetic layer is extended beyond the rear edge part of one of the tunnel barrier layer and the fixed ferromagnetic layer which has the rear edge part nearer to the detection surface. The direction of magnetization of the fixed ferromagnetic layer is desirably fixed in the direction of an arrow 119 approximately perpendicular to the detection surface, namely, the magnetic recording medium by surface exchange coupling with an antiferromagnetic layer.;COPYRIGHT: (C)1999,JPO