Tunneling magnetoresistive device and method for manufacturing the same
AssigneeAlps Electric Co., Ltd.
InventorsMakoto Nakazawa, Takashi Hatanai
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Abstract
A tunneling magnetoresistive device comprises an insulating barrier layer, and at least two ferromagnetic layers provided on the same plane of the layer. The insulating barrier layer can be initially formed, so that when a metal layer is oxidized to form the insulating barrier layer, it is unnecessary to pay care to the influence of oxidation on the ferromagnetic layers. The insulating barrier layer can be formed in large thickness, thereby suppressing defects, such as pinholes, from occurring. Thus, a tunneling magnetoresistive device having good characteristics can be manufactured.
Claims29
A tunneling magnetoresistive device, comprising:
- an insulating barrier layer;
- at least two ferromagnetic layers provided on the insulating barrier layer and arranged side by side along the surface of the insulating barrier layer;
- and a pair of electrode layers, wherein at least the two ferromagnetic layers are kept away from each other at a given space sufficient to show a tunnel effect so that an electric current passing from one of the electrode layers toward one of at least the two ferromagnetic layers is allowed to pass via the insulating barrier layer to the other ferromagnetic layer.
A method for manufacturing a tunneling magnetoresistive device, comprising the steps of:
- (a) forming a metal layer on a substrate;
- (b) forming an insulating barrier layer by oxidation of the metal layer;
- (c) forming a ferromagnetic layer on the insulating barrier layer;
- and
- (d) forming, in the ferromagnetic layer, a space sufficient to show a tunnel effect so that an electric current tunnels within the insulating barrier layer.
A method for manufacturing a tunneling magnetoresistive device, comprising the steps of:
- (e) forming an insulating barrier layer of a paramagnetic insulator made of a perovskite-type oxide represented by R1-xAxMnO3 wherein R represents one or more elements selected from trivalent rare earth metal ions such as La3+, Pr3+, Nd3+, A represents one or more elements selected from divalent alkaline earth metal ions such as Ca2+, Sr2+, Ba2+, and X is a compositional ratio;
- (f) forming a ferromagnetic layer made of either a ferromagnetic metal or half metal consisting of R1-xAxMnO3 wherein R represents one or more elements selected from trivalent rare earth metal ions such as La3+, Pr3+, Nd3+, A represents one or more elements selected from divalent alkaline earth metal ions such as Ca2+, Sr2+, Ba2+, and X is a compositional ratio;
- and
- (g) forming, in the ferromagnetic layer, a space sufficient to show a tunnel effect so that an electric current tunnels within the insulating barrier layer.
Dependencies are inferred from the claim text.