Patent ID: 7397639

Claim:
A magnetic detecting element having a multi-layer film comprising: a lower gap layer made up of an insulating material, a seed layer formed on the lower gap layer, a pinned magnetic layer formed directly on the seed layer, a nonmagnetic material layer formed on the pinned magnetic layer, a free magnetic layer formed on the nonmagnetic material layer, and a protective layer formed on the free magnetic layer, wherein the pinned magnetic layer has a layered-ferri configuration including a first pinned magnetic layer and a second pinned magnetic layer which are made up of a magnetic material and layered with a first nonmagnetic intermediate layer situated therebetween, the first pinned magnetic layer and the second pinned magnetic layer have positive magnetostriction, and the magnetization direction of each of the first and second pinned magnetic layers is pinned in a uniaxial direction by its uniaxial anisotropy, and first and second electrode layers are formed on both sides of the multi-layer film so that a sensing current flows in a direction parallel to the film surfaces of the pinned magnetic layer, the nonmagnetic material layer, and the free magnetic layer via the first and second electrode layers, wherein the free magnetic layer has a layered-ferri configuration in which a first free magnetic layer and a second free magnetic layer, which comprise a magnetic material, are layered with a second nonmagnetic intermediate layer situated therebetween, and a magnetic film thickness of the second free magnetic layer in contact with the nonmagnetic material layer is greater than a magnetic film thickness of the first free magnetic layer, wherein a ratio between the magnetic film thickness of the first free magnetic layer and the magnetic film thickness of the second free magnetic layer (the magnetic film thickness of the first free magnetic layer/the magnetic film thickness of the second free magnetic layer) is between 1/5 and 3/5 inclusive.