US 6,583,969 B1 · Pinned layer structure having nickel iron film for reducing coercivity of a free layer structure in a spin valve sensor

Abstract

A pinned layer structure includes a nickel iron (NiFe) film which lowers the coercivity HC of the pinned layer structure as well as the coercivity HC of a free layer structure within a spin valve sensor, thereby promoting return of a magnetic moment of the pinned layer structure to its original orientation after being rotated therefrom and promoting a freer rotation of the magnetic moment of the free layer structure in response to signal fields from a rotating magnetic disk. In a preferred embodiment the pinned layer structure is an antiparallel (AP) pinned layer structure which has an antiparallel coupling layer located between first and second AP pinned layers. In a first embodiment the first AP pinned layer is composed of a nickel iron (NiFe) film and a cobalt iron (CoFe) film with the nickel iron (NiFe) film located between a pinning layer and the cobalt iron (CoFe) film, and in a second embodiment the first AP pinned layer includes another cobalt iron (CoFe) film which is located between the pinning layer and the nickel iron (NiFe) film. In the preferred embodiment the pinning layer is composed of platinum manganese (PtMn).

Claims48

Dependent claims

A magnetic read head comprising:

a spin valve sensor including:
a ferromagnetic free layer structure that has a magnetic moment;
a ferromagnetic pinned layer structure that has a magnetic moment;
a nonmagnetic conductive spacer layer located between the free layer structure and the pinned layer structure;
an antiferromagnetic metallic pinning layer exchange coupled to the pinned layer structure for pinning the magnetic moment of the pinned layer structure;
the pinned layer structure including first and second cobalt based films and a nickel iron (NiFe) film with the nickel iron (NiFe) film being located between and interfacing the first and second cobalt (Co) based films;
and
the first cobalt (Co) based film interfacing the metallic pinning layer.

5 more elements

A magnetic head assembly comprising:

a write head including:
ferromagnetic first and second pole piece layers wherein each of the first and second pole piece layers has a pole tip portion, a yoke portion and a back gap portion with the yoke portion located between the pole tip portion and the 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, a read head including:
a spin valve sensor;
first and second hard bias and lead layers connected to the valve sensor;
nonmagnetic nonconductive first and second read gap layers;
the spin valve sensor and the first and second hard bias and lead layers being located between the first and second read gap layers;
a ferromagnetic first shield layer;
and
the first and second gap layers being located between the first shield layer and the first pole piece layer;
the spin valve sensor including:
a ferromagnetic free layer structure that has a magnetic moment;
a ferromagnetic pinned layer structure that has a magnetic moment;
a nonmagnetic conductive spacer layer located between the free layer structure and the pinned layer structure;
an antiferromagnetic metallic pinning layer exchange coupled to the pinned layer structure for pinning the magnetic moment of the pinned layer structure;
the pinned layer structure including first and second cobalt based films and a nickel iron (NiFe) film with the nickel iron (NiFe) film being located between and interfacing the first and second cobalt (Co) based films;
and
the first cobalt (Co) based film interfacing the metallic pinning layer.

18 more elements

A magnetic disk drive having a magnetic head assembly wherein the magnetic head assembly has a write head and a read head, comprising:

the write head including:
ferromagnetic first and second pole piece layers wherein each of the first and second pole piece layers has a pole tip portion, a yoke portion and a back gap portion with the yoke portion located between the pole tip portion and the 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;
the read head including:
a spin valve sensor;
first and second hard bias and lead layers connected to the spin valve sensor;
nonmagnetic nonconductive first and second read gap layers;
the spin valve sensor being located between the first and second read gap layers;
a ferromagnetic first shield layer;
and
the first and second read gap layers being located between the first shield layer
and the first pole piece layer;
the spin valve sensor including:
a ferromagnetic free layer structure that has a magnetic moment;
a ferromagnetic pinned layer structure that has a magnetic moment;
a nonmagnetic conductive spacer layer located between the free layer structure and the pinned layer structure;
an antiferromagnetic metallic pinning layer exchange coupled to the pinned layer structure for pinning the magnetic moment of the pinned layer structure;
the pinned layer structure including first and second cobalt based films and a nickel iron (NiFe) film with the nickel iron (NiFe) film being located between and interfacing the first and second cobalt (Co) based films;
and
the first cobalt (Co) based film interfacing the metallic pinning layer;
a housing;
a magnetic disk rotatably supported in the housing;
a support mounted in the housing for supporting the magnetic head assembly with a head surface of the magnetic head assembly 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 positioning means 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.

27 more elements

A method of making a magnetic read head comprising the steps of:

making a spin valve sensor as follows:
forming a ferromagnetic free layer structure that has a magnetic moment;
forming a ferromagnetic pinned layer structure that has a magnetic moment;
forming a nonmagnetic conductive spacer layer between the free layer structure and the pinned layer structure;
forming an antiferromagnetic metallic pinning layer exchange coupled to the pinned layer structure for pinning the magnetic moment of the pinned layer structure;
forming the pinned layer structure with first and second cobalt based films and a nickel iron (NiFe) film with the nickel iron (NiFe) film being located between and interfacing the first and second cobalt (Co) based films;
and
forming the first cobalt (Co) based film interfacing the metallic pinning layer.

5 more elements

A method of making a magnetic head assembly comprising the steps of:

making a write head comprising the steps of:
forming ferromagnetic first and second pole piece layers in pole tip, yoke and back gap regions wherein the yoke region is located between the pole tip and back gap regions;
forming a nonmagnetic nonconductive write gap layer between the first and second pole piece layers in the pole tip region;
forming an insulation stack with at least one coil layer embedded therein between the first and second pole piece layers in the yoke region;
and
connecting the first and second pole piece layers at said back gap region;
making a read head as follows:
forming a spin valve sensor;
connecting first and second hard bias and lead layers to the spin valve sensor;
forming nonmagnetic nonconductive first and second read gap layers;
forming the spin valve sensor and the first and second hard bias and lead layers between the first and second read gap layers;
forming a ferromagnetic first shield layer;
and
forming the first and second read gap layers between the first shield layer and the first pole piece layer;
and a making of the spin valve sensor including:
forming a ferromagnetic free layer structure that has a magnetic moment;
forming a ferromagnetic pinned layer structure that has a magnetic moment;
forming a nonmagnetic conductive spacer layer between the free layer structure and the pinned layer structure;
forming an antiferromagnetic metallic pinning layer exchange coupled to the first pinned layer structure for pinning the magnetic moment of the pinned layer structure;
forming the pinned layer structure with first and second cobalt based films and a nickel iron (NiFe) film with the nickel iron (NiFe) film being located between and interfacing the first and second cobalt (Co) based films;
and
forming the first cobalt (Co) based film interfacing the metallic pinning layer.

19 more elements

A magnetic read head comprising:

a spin valve sensor that includes:
a ferromagnetic free layer structure that has a magnetic moment;
nonmagnetic electrically conductive first and second spacer layers;
the free layer structure being located between the first and second spacer layers;
first and second antiparallel (AP) pinned layer structures;
the first and second spacer layers being located between the first and second AP pinned layer structures;
the first AP pinned layer structure including a first antiparallel AP coupling layer and ferromagnetic first and second antiparallel (AP) pinned layers with the first AP coupling layer being located between and interfacing the first and second AP pinned layers;
the second AP pinned layer structure including a second antiparallel AP coupling layer and ferromagnetic third and fourth antiparallel (AP) pinned layers with the second AP coupling layer being located between and interfacing the third and fourth AP pinned layers;
the second and fourth AP pinned layers consisting of a cobalt (Co) based material and interfacing the first and second spacer layers respectively;
the first AP pinned layer including ferromagnetic first, second and third films with the second film being located between and interfacing the first and third films and the third AP pinned layer including ferromagnetic fourth, fifth and sixth films with the fifth film being located between and interfacing the fourth and sixth films;
the second and fifth films being nickel iron (NiFe) based and the first, third, fourth and sixth films being cobalt based;
antiferromagnetic first and second metallic pinning layers;
and
the first pinning layer interfacing the first film for pinning a magnetic moment of the first AP pinned layer and the second pinning layer interfacing the fourth film for pinning a magnetic moment of the third AP pinned layer.

11 more elements

A magnetic head assembly comprising:

a write head including:
ferromagnetic first and second pole piece layers wherein each of the first and second pole piece layers has a pole tip portion, a yoke portion and a back gap portion with the yoke portion located between the pole tip portion and the 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;
a read head including:
a spin valve sensor;
first and second hard bias and lead layers connected to the valve sensor;
nonmagnetic nonconductive first and second read gap layers;
the spin valve sensor and the first and second hard bias and lead layers being located between the first and second read gap layers;
a ferromagnetic first shield layer;
and
the first and second read gap layers being located between the first shield layer and the first pole piece layer;
the spin valve sensor including:
a ferromagnetic free layer structure that has a magnetic moment;
nonmagnetic electrically conductive first and second spacer layers;
the free layer structure being located between the first and second spacer layers;
first and second antiparallel (AP) pinned layer structures;
the first and second spacer layers being located between the first and second AP pinned layer structures;
the first AP pinned layer structure including a first antiparallel AP coupling layer and ferromagnetic first and second antiparallel (AP) pinned layers with the first AP coupling layer being located between and interfacing the first and second AP pinned layers;
the second AP pinned layer structure including a second antiparallel AP coupling layer and ferromagnetic third and fourth antiparallel (AP) pinned layers with the second AP coupling layer being located between and interfacing the third and fourth AP pinned layers;
the second and fourth AP pinned layers consisting of a cobalt (Co) based material and interfacing the first and second spacer layers respectively;
the first AP pinned layer including ferromagnetic first, second and third films with the second film being located between and interfacing the first and third films and the third AP pinned layer including ferromagnetic fourth, fifth and sixth films with the fifth film being located between and interfacing the fourth and sixth films;
the second and fifth films being nickel iron (NiFe) based and the first, third, fourth and sixth films being cobalt based;
antiferromagnetic first and second metallic pinning layers;
and
the first pinning layer interfacing the first film for pinning a magnetic moment of the first AP pinned layer and the second pinning layer interfacing the fourth film for pinning a magnetic moment of the third AP pinned layer.

25 more elements

A magnetic disk drive having a magnetic head assembly wherein the magnetic head assembly has a write head and a read head, comprising:

the write head including:
ferromagnetic first and second pole piece layers wherein each of the first and second pole piece layers has a pole tip portion, a yoke portion and a back gap portion with the yoke portion located between the pole tip portion and the 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;
the read head including:
a spin valve sensor;
first and second hard bias and lead layers connected to the spin valve sensor;
nonmagnetic nonconductive first and second read gap layers;
the spin valve sensor being located between the first and second read gap layers;
a ferromagnetic first shield layer;
and
the first and second read gap layers being located between the first shield layer and the first pole piece layer;
the spin valve sensor including:
a ferromagnetic free layer structure that has a magnetic moment;
nonmagnetic electrically conductive first and second spacer layers;
the free layer structure being located between the first and second spacer layers;
first and second antiparallel (AP) pinned layer structures;
the first and second spacer layers being located between the first and second AP pinned layer structures;
the first AP pinned layer structure including a first antiparallel AP coupling layer and ferromagnetic first and second antiparallel (AP) pinned layers with the first AP coupling layer being located between and interfacing the first and second AP pinned layers;
the second AP pinned layer structure including a second antiparallel AP coupling layer and ferromagnetic third and fourth antiparallel (AP) pinned layers with the second AP coupling layer being located between and interfacing the third and fourth AP pinned layers;
the second and fourth AP pinned layers consisting of a cobalt (Co) based material and interfacing the first and second spacer layers respectively;
the first AP pinned layer including ferromagnetic first, second and third films with the second film being located between and interfacing the first and third films and the third AP pinned layer including ferromagnetic fourth, fifth and sixth films with the fifth film being located between and interfacing the fourth and sixth films;
the second and fifth films being nickel iron (NiFe) based and the first, third, fourth and sixth films being cobalt based;
antiferromagnetic first and second metallic pinning layers;
and
the first pinning layer interfacing the first film for pinning a magnetic moment of the first AP pinned layer and the second pinning layer interfacing the fourth film for pinning a magnetic moment of the third AP 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 a head surface of the magnetic head assembly 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 positioning means 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.

32 more elements

A method of making a magnetic read head comprising the steps of:

making a spin valve sensor that includes the steps of:
forming a ferromagnetic free layer structure that has a magnetic moment;
forming nonmagnetic electrically conductive first and second spacer layers;
forming the free layer structure between the first and second spacer layers;
forming first and second antiparallel (AP) pinned layer structures;
forming the first and second spacer layers between the first and second AP pinned layer structures;
forming the first AP pinned layer structure with a first antiparallel AP coupling layer and ferromagnetic first and second antiparallel (AP) pinned layers with the first AP coupling layer located between and interfacing the first and second AP pinned layers;
forming the second AP pinned layer structure with a second antiparallel AP coupling layer and ferromagnetic third and fourth antiparallel (AP) pinned layers with the second AP coupling layer located between and interfacing the third and fourth AP pinned layers;
forming the second and fourth AP pinned layers of only a cobalt (Co) based material and interfacing the second and fourth AP pinned layers with the first and second spacer layers respectively;
forming the first AP pinned layer with ferromagnetic first, second and third films with the second film located between and interfacing the first and third films and the third AP pinned layer with ferromagnetic fourth, fifth and sixth films with the fifth film located between and interfacing the fourth and sixth films;
forming the second and fifth films nickel iron (NiFe) based and the first, third, fourth and sixth films cobalt based;
forming antiferromagnetic first and second metallic pinning layers;
and
forming the first pinning layer interfacing the first film for pinning a magnetic moment of the first AP pinned layer and the second pinning layer interfacing the fourth film for pinning a magnetic moment of the third AP pinned layer.

11 more elements

A method of making a magnetic head assembly comprising the steps of:

making a write head comprising the steps of:
forming ferromagnetic first and second pole piece layers in pole tip, yoke and back gap regions wherein the yoke region is located between the pole tip and back gap regions;
forming a nonmagnetic nonconductive write gap layer between the first and second pole piece layers in the pole tip region;
forming an insulation stack with at least one coil layer embedded therein between the first and second pole piece layers in the yoke region;
and
connecting the first and second pole piece layers at said back gap region;
making a read head comprising the steps of:
forming a spin valve sensor;
connecting first and second hard bias and lead layers to the spin valve sensor;
forming nonmagnetic nonconductive first and second read gap layers;
forming the spin valve sensor and the first and second hard bias and lead layers between the first and second read gap layers;
forming a ferromagnetic first shield layer;
and
forming the first and second read gap layers between the first shield layer and the first pole piece layer;
and
a making of the spin valve sensor comprising the steps of:
forming a ferromagnetic free layer structure that has a magnetic moment;
forming nonmagnetic electrically conductive first and second spacer layers;
forming the free layer structure between the first and second spacer layers;
forming first and second antiparallel (AP) pined layer structures;
forming the first and second spacer layers between the first and second AP pinned layer structures;
forming the first AP pinned layer structure with a first antiparallel AP coupling layer and ferromagnetic first and second antiparallel (AP) pinned layers with the first AP coupling layer located between and interfacing the first and second AP pinned layers;
forming the second AP pinned layer structure with a second antiparallel AP coupling layer and ferromagnetic third and fourth antiparallel (AP) pinned layers with the second AP coupling layer located between and interfacing the third and fourth AP pinned layers;
forming the second and fourth AP pinned layers of only a cobalt (Co) based material and interfacing the second and fourth AP pinned layers with the first and second spacer layers respectively;
forming the first AP pinned layer with ferromagnetic first, second and third films with the second film located between and interfacing the first and third films and the third AP pinned layer with ferromagnetic fourth, fifth and sixth films with the fifth film located between and interfacing the fourth and sixth films;
forming the second and fifth films nickel iron (NiFe) based and the first, third, fourth and sixth films cobalt based;
forming antiferromagnetic first and second metallic pinning layers;
and
forming the first pinning layer interfacing the first film for pinning a magnetic moment of the first AP pinned layer and the second pinning layer interfacing the fourth film for pinning a magnetic moment of the third AP pinned layer.

26 more elements

Dependencies are inferred from the claim text.

Pinned layer structure having nickel iron film for reducing coercivity of a free layer structure in a spin valve sensor

Life of this patent

Pinned layer structure having nickel iron film for reducing coercivity of a free layer structure in a spin valve sensor

Life of this patent

Abstract

Claims48