Magnetoresistive element

• US 8,604,569 B2
• Filed: 10/01/2008
• Issued: 12/10/2013
• Est. Priority Date: 10/03/2007
• Status: Expired due to Fees

• Current Assignee: Kioxia Corporation
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Hosotani, Keiji, Asao, Yoshiaki
• Primary Examiner(s): Nguyen, Vanthu
• Assistant Examiner(s): NGUYEN, HIEN N
• Application Number:
  US12/243,250
• Publication Number:
  US 20090091863A1
• Time in Patent Office: 1,896 Days
• Field of Search: 257/421, 257/422, 257/427, 257/E27.006, 365/158
• US Class Current: 257/421
• CPC Class Codes: B82Y 25/00 Nanomagnetism, e.g. magnetoimpedance, anisotropic magnetoresistance, giant magnetoresistance or tunneling magnetoresistance
• CPC Class Codes: G11C 11/161 details concerning the memory cell structure, e.g. the layers of the ferromagnetic memory cell
• CPC Class Codes: H01F 10/1933 Perovskites
• CPC Class Codes: H01F 10/3254 the spacer being semiconducting or insulating, e.g. for spin tunnel junction [STJ]
• CPC Class Codes: H01F 10/3263 the exchange coupling being symmetric, e.g. for dual spin valve, e.g. NiO/Co/Cu/Co/Cu/Co/NiO
• CPC Class Codes: H01F 10/3286 Spin-exchange coupled multilayers having at least one layer with perpendicular magnetic anisotropy
• CPC Class Codes: H10B 61/22 of the field-effect transistor [FET] type
• CPC Class Codes: H10N 50/10 Magnetoresistive devices
• CPC Class Codes: H10N 50/85 Magnetic active materials

Abstract

A magnetoresistive element includes a first electrode layer, a first fixed layer provided on the first electrode layer and having a fixed magnetization direction, a first intermediate layer provided on the first fixed layer and made of a metal oxide, a free layer provided on the first intermediate layer and having a variable magnetization direction, and a second electrode layer provided on the free layer. At least one of the first electrode layer and the second electrode layer contains a conductive metal oxide.

Claims

1. A magnetoresistive element comprising:

a first electrode layer;

a first fixed layer provided on the first electrode layer and having a fixed magnetization direction;

a first intermediate layer provided on the first fixed layer and made of magnesium oxide;

a free layer provided on the first intermediate layer and having a variable magnetization direction; and

a second electrode layer provided on the free layer,

wherein the first electrode layer and the second electrode layer contain a conductive metal oxide, and

oxygen is supplied to the first intermediate layer from the first and second electrode layers which are not in contact with the first intermediate layer.

2. The magnetoresistive element according to claim 1, wherein the conductive metal oxide is an NaCl-type metal oxide, a spinel-type metal oxide, a perovskite-ReO₃-type metal oxide, a corundum-type metal oxide or a rutile-MoO₂-type metal oxide.

3. The magnetoresistive element according to claim 1, further comprising:

a second intermediate layer provided on the free layer and made of a nonmagnetic material; and

a second fixed layer provided on the second intermediate layer and having a fixed magnetization direction.

4. The magnetoresistive element according to claim 3, wherein the second intermediate layer is made of copper (Cu), aluminum (Al), silver (Ag) or gold (Au).

5. The magnetoresistive element according to claim 1, wherein at least one of the fixed layer and the free layer is formed by laminating a first magnetic layer, a nonmagnetic layer and a second magnetic layer in this order.

6. The magnetoresistive element according to claim 1, the first fixed layer, the first intermediate layer and the free layer have the same crystalline orientation.