Magnetic sensing element including second free magnetic layer extending wider than track width and method for fabricating same
AssigneeAlps Electric Co., Ltd.
InventorsNaoya Hasegawa, Eiji Umetsu
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Abstract
Disclosed are a CPP magnetic sensing element employing the exchange bias method in which a sensing current is prevented from expanding in the track width direction in the multilayer film while the magnetization of the free magnetic layer is controlled properly, side reading is effectively prevented, and read output is improved, and a method for fabricating the same. First insulating layers are disposed at both sides in the track width direction of a multilayer film, a second free magnetic layer is disposed over the multilayer film and the first insulating layers, and second antiferromagnetic layers are disposed on both side regions of the second free magnetic layer.
Claims20
A magnetic sensing element comprising:
- a lower electrode layer;
- a multilayer film comprising a first antiferromagnetic layer, a pinned magnetic layer, a nonmagnetic material layer, and a first free magnetic layer deposited in that order on the lower electrode layer;
- first insulating layers disposed on both end faces in the track width direction.of the multilayer film;
- a second free magnetic layer disposed over the first insulating layers and the first free magnetic layer;
- second antiferromagnetic layers disposed on both side regions of the second free magnetic layer facing the first insulating layers in the thickness direction;
- and
- an upper electrode layer disposed over the second antiferromagnetic layers and the second free magnetic layer exposed to a space between the second antiferromagnetic layers in the track width direction.
A method for fabricating a magnetic sensing element comprising the steps of:
- (a) forming a multilayer film on a lower electrode layer, the multilayer film comprising a first antiferromagnetic layer, a pinned magnetic layer, a nonmagnetic material layer, and a first free magnetic layer deposited in that order from the bottom;
- (b) trimming both end faces in the track width direction of the multilayer film and forming first insulating layers on the end faces;
- (c) forming a second free magnetic layer over the first insulating layers and the first free magnetic layer;
- (d) forming second antiferromagnetic layers on both side regions of the second free magnetic layer facing the first insulating layers in the thickness direction;
- and
- (e) forming an upper electrode layer over the second antiferromagnetic layers and the second free magnetic layer exposed to a space between the antiferromagnetic layers in the track width direction.
A method for fabricating a magnetic sensing element comprising the steps of:
- (a) forming a multilayer film on a lower electrode layer, the multilayer film comprising a first antiferromagnetic layer, a pinned magnetic layer, a nonmagnetic material layer, and a first free magnetic layer deposited in that order from the bottom;
- (b) trimming both end faces in the track width direction of the multilayer film and forming first insulating layers on the end faces;
- (c) forming a second free magnetic layer over the first insulating layers and the first free magnetic layer;
- (f) forming a second antiferromagnetic layer and a second insulating layer on the second free magnetic layer;
- (g) forming a mask layer on the side regions of the second insulating layer corresponding to the first insulating layers in the thickness direction, and removing the central regions of the second insulating layer and the second antiferromagnetic layer not covered with the mask layer to expose the upper surface of the second free magnetic layer to a space between the side regions of the second insulating layer;
- and
- (e) forming an upper electrode layer over the second antiferromagnetic layers and the second free magnetic layer exposed to a space between the antiferromagnetic layers in the track width direction.
Dependencies are inferred from the claim text.