Patent ID: 7397637

Claim:
A magnetic head, comprising: an in-stack bias structure, comprising an antiferromagnetic layer; a first bias layer positioned above the antiferromagnetic layer, a magnetic moment of the first bias layer being pinned by the antiferromagnetic layer; a first antiparallel coupling layer positioned adjacent the first bias layer; a second bias layer positioned adjacent the first antiparallel coupling layer and having a magnetic moment pinned antiparallel to the magnetic moment of the first bias layer; a second antiparallel coupling layer positioned adjacent the second bias layer; a third bias layer positioned adjacent the second antiparallel coupling layer and having a magnetic moment pinned antiparallel to the magnetic moment of the second bias layer; a third antiparallel coupling layer positioned adjacent the third bias layer; a fourth bias layer positioned adjacent the third antiparallel coupling layer and having a magnetic moment pinned antiparallel to the magnetic moment of the third bias layer; a first spacer layer positioned above the fourth bias layer of the bias structure; and a free layer positioned above the first spacer layer, wherein the fourth bias layer magnetostatically stabilizes the free layer.