Specular spin valve with robust pinned layer
AssigneeHeadway Technologies, Inc.
InventorsCheng T. Horng, Min Li, Ru-Ying Tong, Rong-Fu Xiao
Life of this patent
Estimating the term…
Abstract
A specular spin valve structure that is more robust than currently available specular spin valves is described. The improved stability is achieved by a using a modified pinned layer that is a laminate of three layers—a layer nickel-chromium, between about 3 and 4 Angstroms thick, sandwiched between two layers of cobalt-iron. A key requirement is that the cobalt-iron layer closest to the copper separation layer must be about twice as thick as the other cobalt-iron layer. A process for manufacturing this structure is also disclosed.
Claims20
A process for manufacturing a spin valve structure, comprising:
- providing a substrate;
- on said substrate, depositing a magneto-resistance enhancing seed layer;
- depositing a free layer that further comprises a first layer of nickel-iron on the magneto-resistance enhancing seed layer and a first layer of cobalt-iron on the first nickel-iron layer;
- depositing a layer of copper on the free layer;
- depositing a laminated pinned layer that further comprises a second layer of cobalt-iron, between about 10 and 15 Angstroms thick, on the copper layer, a layer nickel-chromium, between about 3 and 4 Angstroms thick, on the second layer of cobalt-iron, and a third layer of cobalt iron, between about 5 and 7 Angstroms thick, on the layer of nickel-chromium, whereby the thickness of said second layer of cobalt-iron is about twice the thickness of the third layer of cobalt-iron;
- depositing a pinning layer on the laminated pinned layer;
- depositing a cap layer on the pinning layer;
- and
- then annealing.
A pinned layer laminate, forming part of a specular spin valve structure, comprising:
- a first layer of cobalt-iron, between about 10 and 15 Angstroms thick:
- a layer of nickel-chromium, between about 3 and 4 Angstroms thick, on said first layer of cobalt-iron;
- and
- a second layer of cobalt-iron, between about 5 and 7 Angstroms thick, on the layer of nickel-chromium, whereby the thickness of said first layer of cobalt-iron is about twice the thickness of said second layer of cobalt-iron.
A spin valve structure, comprising:
- a substrate;
- on said substrate, a magneto-resistance enhancing seed layer;
- a free layer that further comprises a first layer of nickel-iron on the magneto-resistance enhancing seed layer and a first layer of cobalt-iron on the first nickel-iron layer;
- a layer of copper on the free layer;
- a laminated pinned layer that further comprises a second layer of cobalt-iron, between about 10 and 15 Angstroms thick, on the copper layer, a layer of nickel-chromium, between about 3 and 4 Angstroms thick, on the second layer of cobalt-iron, and a third layer of cobalt iron, between about 5 and 7 Angstroms thick, on the layer of nickel-chromium, whereby the thickness of said second layer of cobalt-iron is about twice the thickness of the third layer of cobalt-iron;
- a pinning layer on the laminated pinned layer;
- and
- a cap layer on the pinning layer.
Dependencies are inferred from the claim text.