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US 6,721,139 B2Granted
Tunnel valve sensor with narrow gap flux guide employing a lamination of FeN and NiFeMo
AssigneeInternational Business Machines Corporation
InventorHardayal Singh Gill
Life of this patent
Estimating the term…
Abstract
A tunnel valve sensor has a flux guide which has at least one iron nitride (FeN) layer and preferably a lamination of iron nitride (FeN) and nickel iron molybdenum (NiFeMo) layers wherein in the first instance the read gap is reduced and in the second instance the read gap is reduced and the sensitivity of the read head is increased.
Claims26
A magnetic head assembly which has an air bearing surface (ABS), comprising:
- a read head including:
- a tunnel valve sensor having front and back walls wherein the front wall is recessed from the ABS and is located between the ABS and the back wall;
- a flux guide having front and back walls wherein the front wall is located at the ABS and the back wall is located between the ABS and the front wall of the tunnel valve sensor;
- an electrically nonconductive first insulation layer located between and interfacing the front wall of the tunnel valve sensor and the back wall of the flux guide;
- and
- the flux guide being a lamination of iron nitride (FeN) and nickel iron molybdenum (NiFeMo) layers.
3 more elements
A magnetic head assembly which has an air bearing surface (ABS), comprising:
- a read head including:
- a tunnel valve sensor having front and back walls wherein the front wall is recessed from the ABS and is located between the ABS and the back wall;
- a flux guide having front and back walls wherein the front wall is located at the ABS and the back wall is located between the ABS and the front wall of the tunnel valve sensor;
- an electrically nonconductive first insulation layer located between and interfacing the front wall of the tunnel valve sensor and the back wall of the flux guide;
- ferromagnetic first and second shield layers;
- the tunnel valve sensor and the flux guide being located between the first and second shield layers;
- and
- electrically nonconductive second and third insulation layers located between the first shield layer and the flux guide and between the second shield layer and the flux guide respectively;
- the tunnel value sensor including:
- a ferromagnetic pinned layer that has a magnetic moment;
- an antiferromagnetic pinning layer exchange coupled to the pinned layer for pinning the magnetic moment of the pinned layer;
- a ferromagnetic free layer which has a magnetic moment;
- a nonmagnetic electrically insulative barrier layer located between the free layer and the pinned layer;
- the flux guide consisting of one iron nitride (FeN) layer and one nickel molybdenum (NiFeMo) layer.
11 more elements
A magnetic head assembly which has an air bearing surface (ABS), comprising:
- a read head including:
- a tunnel valve sensor having front and back walls wherein the front wall is recessed from the ABS and is located between the ABS and the back wall;
- a flux guide having front and back walls wherein the front wall is located at the ABS and the back wall is located between the ABS and the front wall of the tunnel valve sensor;
- an electrically nonconductive first insulation layer located between and interfacing the front wall of the tunnel valve sensor and the back wall of the flux guide;
- ferromagnetic first and second shield layers;
- the tunnel valve sensor and the flux guide being located between the first and second shield layers;
- and
- electrically nonconductive second and third insulation layers located between the first shield layer and the flux guide and between the second shield layer and the flux guide respectively;
- the tunnel valve sensor including:
- a ferromagnetic pinned layer that has a magnetic moment;
- an antiferromagnetic pinning layer exchange coupled to the pinned layer for pinning the magnetic moment of the pinned layer;
- a ferromagnetic free layer which has a magnetic moment;
- a nonmagnetic electrically insulative barrier layer located between the free layer and the pinned layer;
- the flux guide consisting of three iron nitride (FeN) and two nickel iron molybdenum (NiFeMo) alternating layers.
11 more elements
A magnetic head assembly which has an air bearing surface (ABS), comprising:
- a read head including:
- a tunnel valve sensor having front and back walls wherein the front wall is recessed from the ABS and is located between the ABS and the back wall;
- a flux guide having front and back walls wherein the front wall is located at the ABS and the back wall is located between the ABS and the front wall of the tunnel valve sensor;
- an electrically nonconductive first insulation layer located between and interfacing the front wall of the tunnel valve sensor and the back wall of the flux guide;
- ferromagnetic first and second shield layers;
- the tunnel valve sensor and the flux guide being located between the first and second shield layers;
- and
- electrically nonconductive second and third insulation layers located between the first shield layer and the flux guide and between the second shield layer and the flux guide respectively;
- the tunnel valve sensor including:
- a ferromagnetic pinned layer that has a magnetic moment;
- an antiferromagnetic pinning layer exchange coupled to the pinned layer for pinning the magnetic moment of the pinned layer;
- a ferromagnetic free layer which has a magnetic moment;
- a nonmagnetic electrically insulative barrier layer located between the free layer and the pinned layer;
- the flux guide consisting of one iron nitride (FeN) layer and one nickel molybdenum (NiFeMo) layer;
- a write head including:
- ferromagnetic first and second pole piece layers that have a yoke portion located between a pole tip portion and a back gap portion;
- a nonmagnetic write gap layer located between the pole tip portions of the first and second pole piece layers;
- an insulation stack with at least one coil layer embedded therein located between the yoke portions of the first and second pole piece layers;
- and
- the first and second pole piece layers being connected at their back gap portions.
17 more elements
A magnetic head assembly which has an air bearing surface (ABS), comprising:
- a read head including:
- a tunnel valve sensor having front and back walls wherein the front wall is recessed from the ABS and is located between the ABS and the back wall;
- a flux guide having front and back walls wherein the front wall is located at the ABS and the back wall is located between the ABS and the front wall of the tunnel valve sensor;
- an electrically nonconductive first insulation layer located between and interfacing the front wall of the tunnel valve sensor and the back wall of the flux guide;
- ferromagnetic first and second shield layers;
- the tunnel valve sensor and the flux guide being located between the first and second shield layers;
- and
- electrically nonconductive second and third insulation layers located between the first shield layer and the flux guide and between the second shield layer and the flux guide respectively;
- the tunnel valve sensor including:
- a ferromagnetic pinned layer that has a magnetic moment;
- an antiferromagnetic pinning layer exchange coupled to the pinned layer for pinning the magnetic moment of the pinned layer;
- a ferromagnetic free layer which has a magnetic moment;
- a nonmagnetic electrically insulative barrier layer located between the free layer and the pinned layer;
- the flux guide consisting of three iron nitride (FeN) and two nickel iron molybdenum (NiFeMo) alternating layers;
- a write head including:
- ferromagnetic first and second pole piece layers that have a yoke portion located between a pole tip portion and a back gap portion;
- a nonmagnetic write gap layer located between the pole tip portions of the first and second pole piece layers;
- an insulation stack with at least one coil layer embedded therein located between the yoke portions of the first and second pole piece layers;
- and
- the first and second pole piece layers being connected at their back gap portions.
17 more elements
A magnetic disk drive including at least one magnetic head assembly that has an a write head, a read head and an air bearing surface (ABS) comprising:
- the write head including:
- ferromagnetic first and second pole piece layers that have a yoke portion located between a pole tip portion and a back gap portion;
- a nonmagnetic write gap layer located between the pole tip portions of the first and second pole piece layers;
- an insulation stack with at least one coil layer embedded therein located between the yoke portions of the first and second pole piece layers;
- the first and second pole piece layers being connected at their back gap portions;
- and
- the read head including:
- a tunnel valve sensor having front and back walls wherein the front wall is recessed from the ABS and is located between the ABS and the back wall;
- a flux guide having front and back walls wherein the front wall is located at the ABS and the back wall is located between the ABS and the front wall of the tunnel valve sensor;
- an electrically nonconductive first insulation layer located between and interfacing the front wall of the tunnel valve sensor and the back wall of the flux guide;
- and
- the flux guide being a lamination of iron nitride (FeN) and nickel iron molybdenum (NiFeMo) layers;
- a ferromagnetic first shield layer;
- the tunnel valve sensor and the flux guide being located between the first shield layer and the first pole piece layer;
- and
- electrically nonconductive second and third insulation layers located between the first shield layer and the flux guide and between the second shield layer and the flux guide respectively;
- the tunnel valve sensor including:
- a ferromagnetic pinned layer that has a magnetic moment;
- an antiferromagnetic pinning layer exchange coupled to the pinned layer for pinning the magnetic moment of the pinned layer;
- a ferromagnetic free layer which has a magnetic moment;
- and
- a nonmagnetic electrically insulative barrier layer located between the free layer and the pinned layer;
- a housing;
- a magnetic disk rotatably supported in the housing;
- a support mounted in the housing for supporting the magnetic head assembly with said ABS facing the magnetic disk so that the magnetic head assembly is in a transducing relationship with the magnetic disk;
- a spindle motor for rotating the magnetic disk;
- an actuator positioning means connected to the support for moving the magnetic head assembly to multiple positions with respect to said magnetic disk;
- and
- a processor connected to the magnetic head assembly, to the spindle motor and to the actuator for exchanging signals with the magnetic head assembly, for controlling movement of the magnetic disk and for controlling the position of the magnetic head assembly.
26 more elements
A method of making a magnetic head assembly which has an air bearing surface (ABS), comprising the steps of:
- making a read head including the steps of:
- forming a tunnel valve sensor having front and back walls wherein the front wall is recessed from the ABS and is located between the ABS and the back wall;
- forming a flux guide having front and back walls wherein the front wall is located at the ABS and the back wall is located between the ABS and the front wall of the tunnel valve sensor;
- forming an electrically nonconductive first insulation layer between and interfacing the front wall of the tunnel valve sensor and the back wall of the flux guide;
- and
- forming the flux guide with a lamination of iron nitride (FeN) and nickel iron molybdenum (NiFeMo) layers.
3 more elements
A method of making a magnetic head assembly which has an air bearing surface (ABS), comprising the steps of:
- making a read head including the steps of:
- forming a tunnel valve sensor having front and back walls wherein the front wall is recessed from the ABS and is located between the ABS and the back wall;
- forming a flux guide having front and back walls wherein the front wall is located at the ABS and the back wall is located between the ABS and the front wall of the tunnel valve sensor;
- forming an electrically nonconductive first insulation layer between and interfacing the front wall of the tunnel valve sensor and the back wall of the flux guide;
- forming ferromagnetic first and second shield layers;
- forming the tunnel valve sensor and the flux guide between the first and second shield layers;
- and
- forming electrically nonconductive second and third insulation layers between the first shield layer and the flux guide and between the second shield layer and the flux guide respectively;
- forming the tunnel valve sensor comprising the steps of:
- forming a ferromagnetic pinned layer that has a magnetic moment;
- forming an antiferromagnetic pinning layer exchange coupled to the pinned layer for pinning the magnetic moment of the pinned layer;
- forming a ferromagnetic free layer which has a magnetic moment;
- and
- forming a nonmagnetic electrically insulative barrier layer between the free layer and the pinned layer;
- and
- forming the flux guide consisting of one iron nitride (FeN) layer and one nickel molybdenum (NiFeMo) layer.
13 more elements
A method of making a magnetic head assembly which has an air bearing surface (ABS), comprising the steps of:
- making a read head including the steps of:
- forming a tunnel valve sensor having front and back walls wherein the front wall is recessed from the ABS and is located between the ABS and the back wall;
- forming a flux guide having front and back wails wherein the front wall is located at the ABS and the back wall is located between the ABS and the front wall of the tunnel valve sensor;
- forming an electrically nonconductive first insulation layer between and interfacing the front wall of the tunnel valve sensor and the back wail of the flux guide;
- forming ferromagnetic first and second shield layers;
- forming the tunnel valve sensor and the flux guide between the first and second shield layers;
- and
- forming electrically nonconductive second and third insulation layers between the first shield layer and the flux guide and between the second shield layer and the flux guide respectively;
- forming the tunnel valve sensor comprising the steps of:
- forming a ferromagnetic pinned layer that has a magnetic moment;
- forming an antiferromagnetic pinning layer exchange coupled to the pinned layer for pinning the magnetic moment of the pinned layer;
- forming a ferromagnetic free layer which has a magnetic moment;
- and
- forming a nonmagnetic electrically insulative barrier layer between the free layer and the pinned layer;
- and
- forming the flux guide consisting of three iron nitride (FeN) and two nickel iron molybdenum (NiFeMo) alternating layers.
13 more elements
A method of making a magnetic head assembly which has an air bearing surface (ABS), comprising the steps of:
- making a read head including the steps of:
- forming a tunnel valve sensor having front and back walls wherein the front wall is recessed from the ABS and is located between the ABS and the back wall;
- forming a flux guide having front and back walls wherein the front wall is located at the ABS and the back wall is located between the ABS and the front wall of the tunnel valve sensor;
- forming an electrically nonconductive first insulation layer between and interfacing the front wall of the tunnel valve sensor and the back wall of the flux guide;
- forming ferromagnetic first and second shield layers;
- forming the tunnel valve sensor and the flux guide between the first and second shield layers;
- and
- forming electrically nonconductive second and third insulation layers between the first shield layer and the flux guide and between the second shield layer and the flux guide respectively;
- forming the tunnel valve sensor comprising the steps of:
- forming a ferromagnetic pinned layer that has a magnetic moment;
- forming an antiferromagnetic pinning layer exchange coupled to the pinned layer for pinning the magnetic moment of the pinned layer;
- forming a ferromagnetic free layer which has a magnetic moment;
- and
- forming a nonmagnetic electrically insulative barrier layer between the free layer and the pinned layer;
- forming the flux guide consisting of one iron nitride (FeN) layer and one nickel molybdenum (NiFeMo) layer;
- forming a write head including the steps of:
- forming ferromagnetic first and second pole piece layers that have a yoke portion located between a pole tip portion and a back gap portion;
- forming a nonmagnetic write gap layer between the pole tip portions of the first and second pole piece layers;
- forming an insulation stack with at least one coil layer embedded therein between the yoke portions of the first and second pole piece layers;
- and
- connecting the first and second pole piece layers at their back gap portions.
18 more elements
A method of making a magnetic head assembly which has an air bearing surface (ABS), comprising the steps of:
- making a read head including the steps of:
- forming a tunnel valve sensor having front and back walls wherein the front wall is recessed from the ABS and is located between the ABS and the back wall;
- forming a flux guide having front and back walls wherein the front wall is located at the ABS and the back wall is located between the ABS and the front wall of the tunnel valve sensor;
- forming an electrically nonconductive first insulation layer between and interfacing the front wall of the tunnel valve sensor and the back wall of the flux guide;
- forming ferromagnetic first and second shield layers;
- forming the tunnel valve sensor and the flux guide between the first and second shield layers;
- and
- forming electrically nonconductive second and third insulation layers between the first shield layer and the flux guide and between the second shield layer and the flux guide respectively;
- forming the tunnel valve sensor comprising the steps of:
- forming a ferromagnetic pinned layer that has a magnetic moment;
- forming an antiferromagnetic pinning layer exchange coupled to the pinned layer for pinning the magnetic moment of the pinned layer;
- forming a ferromagnetic free layer which has a magnetic moment;
- and
- forming a nonmagnetic electrically insulative barrier layer between the free layer and the pinned layer;
- forming the flux guide consisting of three iron nitride (FeN) and two nickel iron molybdenum (NiFeMo) alternating layers;
- forming a write head including the steps of:
- forming ferromagnetic first and second pole piece layers that have a yoke portion located between a pole tip portion and a back gap portion;
- forming a nonmagnetic write gap layer between the pole tip portions of the first and second pole piece layers;
- forming an insulation stack with at least one coil layer embedded therein between the yoke portions of the first and second pole piece layers;
- and
- connecting the first and second pole piece layers at their back gap portions.
18 more elements
Dependencies are inferred from the claim text.