Magnetic recording heads having one or more dusting layers for magnetic recording devices
Embodiments of the present disclosure relate to magnetic recording heads (e.g., magnetic write heads) for magnetic recording devices (e.g., hard disk drives (HDD's)). A magnetic recording head includes, in a gap between a write pole and a trailing shield: a spin polarization layer (SPL), a free layer, and a spacer layer between the SPL and free layer. A spin torque layer (STL) is additionally included, and is separated from the free layer by a barrier layer that reduces or eliminates spin torque between the free layer and the STL. In one or more embodiments, to enable a thinner barrier layer, one or more dusting layers are inserted between the write pole and the trailing shield, and the one or more dusting layers are each formed of iron-chromium (FeCr). This helps maintain a thinner or narrower material stack in the gap and enhances writer performance.
1. A magnetic recording head, comprising:
a write pole;
a trailing shield;
a spin polarizing layer (SPL) between the write pole and the trailing shield, wherein the SPL is ferromagnetic;
a free layer between the write pole and the trailing shield, wherein the free layer is ferromagnetic;
a nonmagnetic spacer layer between the SPL and free layer;
a spin torque layer (STL) between the write pole and the trailing shield, wherein the STL is ferromagnetic and a magnetization of the STL is flippable;
a barrier layer between the free layer and the STL, wherein the barrier layer is nonmagnetic; and
one or more dusting layers between the write pole and the trailing shield, wherein the one or more dusting layers are each formed of iron-chromium (FeCr), wherein the one or more dusting layers further comprise a first set of one or more FeCr layers outwardly of the SPL relative to the free layer, and a second set of one or more FeCr layers between the STL and the free layer.
2. The magnetic recording head of claim 1 , wherein each of the second set of one or more FeCr layers has a thickness that is less than a thickness of each of the first set of one or more FeCr layers.
3. The magnetic recording head of claim 1 , wherein the second set of one or more FeCr layers comprise a first FeCr layer interfacing with a first side of the barrier layer and a second FeCr layer interfacing with a second side of the barrier layer.
4. The magnetic recording head of claim 1 , wherein the first set of one or more FeCr layers are between the SPL and the write pole, the SPL is between the free layer and the write pole, and the STL is between the free layer and the trailing shield.
5. The magnetic recording head of claim 4 , further comprising:
a seed layer between the SPL and the write pole, wherein the seed layer is nonmagnetic, and
wherein the first set of one or more FeCr layers comprise a third FeCr layer interfacing with a first side of the seed layer and a fourth FeCr layer interfacing with a second side of the seed layer.
6. The magnetic recording head of claim 1 , wherein the first set of one or more FeCr layers are between the SPL and the trailing shield, the STL is between the free layer and the write pole, and the SPL is between the free layer and the trailing shield.
7. The magnetic recording head of claim 6 , further comprising:
a capping layer between the SPL and the trailing shield, wherein the capping layer is nonmagnetic, wherein the first set of one or more FeCr layers comprise a third FeCr layer interfacing with a first side of the capping layer and a fourth FeCr layer interfacing with a second side of the capping layer.
8. The magnetic recording head of claim 1 , further comprising electrical circuitry coupled to one or more of the write pole or the trailing shield and configured to generate electron flow between the free layer and the SPL.
9. The magnetic recording head of claim 1 , wherein a thickness of each of the one or more dusting layers is within a range of 0.5 nm to 5.0 nm.
10. The magnetic recording head of claim 1 , wherein an Fe atomic percentage of each of the one or more dusting layers is within a range of 50% to 80%, and a Cr atomic percentage of each of the one or more dusting layers is within a range of 20% to 50%.
11. The magnetic recording head of claim 10 , wherein the Fe atomic percentage and the Cr atomic percentage added together equal at least 95% of a total atomic percentage for each of the one or more dusting layers.
12. A magnetic recording device comprising the magnetic recording head of claim 1 .
13. A magnetic recording head, comprising:
a write pole;
a trailing shield;
a first ferromagnetic layer between the write pole and the trailing shield;
a second ferromagnetic layer between the write pole and the trailing shield;
a third ferromagnetic layer between the write pole and the trailing shield;
a nonmagnetic spacer layer between the first ferromagnetic layer and the third ferromagnetic layer;
a barrier layer between the first ferromagnetic layer and the second ferromagnetic layer, wherein the barrier layer is nonmagnetic;
one or more dusting layers between the write pole and the trailing shield, wherein the one or more dusting layers are each formed of iron-chromium (FeCr), wherein the one or more dusting layers further comprise a first set of one or more FeCr layers outwardly of the third ferromagnetic layer relative to the first ferromagnetic layer, and a second set of one or more FeCr layers between the second ferromagnetic layer and the first ferromagnetic layer; and
electrical circuitry coupled to one or more of the write pole or the trailing shield and configured to generate electron flow between the first ferromagnetic layer and the third ferromagnetic layer.
14. The magnetic recording head of claim 13 , wherein the first ferromagnetic layer is a free layer, the second ferromagnetic layer is a spin torque layer (STL), and the third ferromagnetic layer is a spin polarizing layer (SPL).
15. The magnetic recording head of claim 13 , wherein:
a thickness of each of the second set of one or more FeCr layers is less than 2.0 nm; and
a thickness of each of the first set of one or more FeCr layers is within a range of 2.0 nm to 3.0 nm.
16. A magnetic recording device comprising the magnetic recording head of claim 13 .
17. A magnetic recording head, comprising:
a write pole;
a trailing shield;
a spin polarizing layer (SPL) between the write pole and the trailing shield, wherein the SPL is ferromagnetic;
a free layer between the write pole and the trailing shield, wherein the free layer is ferromagnetic;
a nonmagnetic spacer layer between the SPL and free layer;
a spin torque layer (STL) between the write pole and the trailing shield, wherein the STL is ferromagnetic and a magnetization of the STL is flippable;
a spin torque reducing means between the free layer and the STL for reducing or eliminating spin torque applied to the STL; and
one or more dusting layers between the write pole and the trailing shield, wherein the one or more dusting layers are each formed of iron-chromium (FeCr), wherein the one or more dusting layers comprise a first set of one or more FeCr layers outwardly of the SPL relative to the free layer, and a second set of one or more FeCr layers between the free layer and the STL.
18. A magnetic recording device comprising the magnetic recording head of claim 17 .