Magnetic apparatus with perpendicular recording medium and head having multilayered reproducing element using tunneling effect
View Patent ↗The magnetoresistance effect element is of a multilayered structure having at least magnetic layers and an intermediate layer of an insulating material, a semiconductor or an antiferromagnetic material against the magnetic layers, and the magnetoresistance effect element has terminals formed at least on the opposite magnetic layers, respectively, so that a current flows in the intermediate layer. The film surfaces of all the magnetic layers constituting the magnetoresistance effect element are opposed substantially at right angles to the recording surface of a magnetic recording medium. Therefore, the area of the magnetic layers facing the recording surface of the magnetic recording medium can be extremely reduced, and thus the magnetic field from a very narrow region of the high-density recorded magnetic recording medium can be detected by the current which has a tunneling characteristic and passes through the intermediate layer.
1. A magnetic apparatus, comprising:
a perpendicular magnetic recording medium; and
a magnetic head including a reproducing element arranged to perform reproduction from the perpendicular magnetic recording medium,
wherein said reproducing element has a magnetic-resistance element including a first non-magnetic metal layer, a second non-magnetic metal layer, and a magneto-resistance effect film formed between the first non-magnetic metal layer and the second non-magnetic metal layer,
said magneto-resistance effect film includes a first ferromagnetic layer, a second ferromagnetic layer, an intermediate insulating layer formed between the first ferromagnetic layer and the second ferromagnetic layer, and an anti-ferromagnetic layer formed between the second ferromagnetic layer and the second non-magnetic metal layer, and
said magneto-resistance effect film is arranged so that a tunnel current flows between the first ferromagnetic layer and the second ferromagnetic layer through the intermediate insulating layer.
2. A magnetic apparatus according to claim 1 , wherein a magnetization direction of said first ferromagnetic layer changes in the presence of a changing external magnetic field.
3. A magnetic apparatus according to claim 1 , wherein said perpendicular magnetic recording medium has a perpendicular magnetic recording layer comprising Co—Cr.
4. A magnetic apparatus according to claim 1 , wherein a magnetization direction of said second ferromagnetic layer is fixed by the anti-ferromagnetic layer which applies a bias magnetic field to the second ferromagnetic layer.
5. In a magnetic apparatus of the type having a perpendicular magnetic recording medium and a magnetic bead arranged to perform reproduction from the perpendicular magnetic recording medium, the improvement wherein:
the magnetic head includes a reproducing element,
wherein said reproducing element has a magnetic-resistance element including a first non-magnetic metal layer, a second non-magnetic metal layer, and a magneto-resistance effect film formed between the first non-magnetic metal layer and the second non-magnetic metal layer,
said magneto-resistance effect film includes a first ferromagnetic layer, a second ferromagnetic layer, an intermediate insulating layer formed between the first ferromagnetic layer and the second ferromagnetic layer, and an anti-ferromagnetic layer formed between the second ferromagnetic layer and the second nonmagnetic metal layer, and
said magneto-resistance effect film is arranged so that a tunnel current flows between the first ferromagnetic layer and the second ferromagnetic layer through the intermediate insulating layer.
6. A magnetic apparatus according to claim 5 , wherein a magnetization direction of said first ferromagnetic layer changes in the presence of a changing external magnetic field.
7. A magnetic apparatus according to claim 5 , wherein a magnetization direction of said second ferromagnetic layer is fixed by the anti-ferromagnetic layer which applies a bias magnetic field to the second ferromagnetic layer.