Magnetic head with current assisted magnetic recording and method of making thereof
A magnetic head includes a main pole configured to serve as a first electrode, an upper pole containing a trailing magnetic shield configured to a serve as a second electrode, and a record element located in a trailing gap between the main pole and the trailing magnetic shield. The record element includes an electrically conductive, non-magnetic material portion which is not part of a spin torque oscillator stack. The main pole and the trailing magnetic shield are electrically shorted by the record element across the trailing gap between the main pole and the trailing magnetic shield such that an electrically conductive path is present between the main pole and the trailing magnetic shield through the record element.
1. A magnetic head, comprising:
a main pole configured to serve as a first electrode;
an upper pole comprising a trailing magnetic shield configured to a serve as a second electrode; and
a record element located in a trailing gap between the main pole and the trailing magnetic shield, the record element comprising an electrically conductive, non-magnetic material portion and a spin torque oscillator stack;
wherein the electrically conductive, non-magnetic material portion is not part of the spin torque oscillator stack,
wherein the main pole and the trailing magnetic shield are electrically shorted by the record element across the trailing gap between the main pole and the trailing magnetic shield such that an electrically conductive path is present between the main pole and the trailing magnetic shield through the record element, and
wherein the electrically conductive path comprises a first electrically conductive path between the first electrode and the second electrode through the spin torque oscillator stack, and a parallel second electrically conductive path between the first electrode and the second electrode through the electrically conductive, non-magnetic material portion.
2. The magnetic head of claim 1 , further comprising an electrical bias circuitry configured to flow electrical current between the first electrode and the second electrode through the record element.
3. The magnetic head of claim 2 , further comprising:
a first electrical contact connecting a portion of the main pole distant from an air bearing surface to the electrical bias circuitry;
a second electrical contact connecting a portion of the upper pole distant from the air bearing surface to the electrical bias circuitry; and
an electrically insulating material layer located between the portions of the main pole and the upper pole distal from the air bearing surface.
4. The magnetic head of claim 3 , wherein:
the electrically insulating material layer provides physical and electrical isolation between the portions of the main pole and the upper pole distal from the air bearing surface; and
the only electrically conductive path between the main pole and the upper pole is the electrically conductive path between the main pole and the trailing magnetic shield through the record element.
5. The magnetic head of claim 1 , wherein:
the magnetic head comprises a microwave assisted magnetic recording head; and
an air bearing surface (ABS) of the magnetic head includes planar surfaces of the main pole, the spin torque oscillator stack, and the trailing magnetic shield.
6. The magnetic head of claim 5 , wherein the electrically conductive, non-magnetic material portion is spaced from the air bearing surface by a portion of the trailing magnetic shield and by the spin torque oscillator stack.
7. The magnetic head of claim 6 , wherein the electrically conductive, non-magnetic material portion contacts a leading surface of the trailing magnetic shield.
8. The magnetic head of claim 5 , wherein the record element further comprises a conductive layer stack having a same set of component layers as the spin torque oscillator stack, located within the second electrically conductive path, and spaced from the spin torque oscillator stack by a dielectric spacer.
9. The magnetic head of claim 8 , wherein:
the conductive layer stack and the spin torque oscillator stack are located directly on a trailing sidewall of the main pole;
the electrically conductive, non-magnetic material portion comprises a copper layer located on a trailing sidewall of the conductive layer stack; and
an interface between the spin torque oscillator stack and the trailing magnetic shield is within a same plane as an interface between the conductive layer stack and the electrically conductive, non-magnetic material portion.
10. The magnetic head of claim 5 , further comprising an additional electrically conductive, non-magnetic material portion which is spaced from the air bearing surface by the spin torque oscillator stack.
11. The magnetic head of claim 10 , wherein:
the additional electrically conductive, non-magnetic material portion contacts a trailing sidewall of the main pole and a rear sidewall of the spin torque oscillator stack that is located on an opposite side of the spin torque oscillator from the air bearing surface;
the electrically conductive, non-magnetic material portion is located on a trailing sidewall of the additional electrically conductive, non-magnetic material portion; and
an interface between the spin torque oscillator stack and the trailing magnetic shield is within a same plane as an interface between the additional electrically conductive, non-magnetic material portion and the electrically conductive, non-magnetic material portion.
12. The magnetic head of claim 1 , further comprising an electrical coil that is located adjacent to the main pole and configured to generate a magnetic flux through the main pole upon conduction of electrical current through the electrical coil.
13. A hard disk drive, comprising:
the magnetic head of claim 12 ;
a slider supporting the magnetic head;
an actuator arm supporting the slider;
a voice coil motor configured to control the actuator arm; and
a magnetic disk.
14. A method of operating a magnetic recording head, the method comprising:
providing a current between a main pole and an upper pole containing a trailing magnetic shield through a record element located in a trailing gap between the main pole and the trailing shield while applying a magnetic field to the main pole from a coil to record data to a magnetic disk,
wherein the record element comprises an electrically conductive, non-magnetic material portion which is not part of a spin torque oscillator stack,
wherein the record element further comprises a spin torque oscillator stack,
wherein the current flows through a first electrically conductive path which is present between the main pole and the upper pole through the spin torque oscillator stack, and
wherein the current flows through a parallel second electrically conductive path which is present between the main pole and the upper pole through the electrically conductive, non-magnetic material portion.
15. The method of claim 14 , wherein:
the current is provided through a first electrical contact connecting a portion of the main pole distant from an air bearing surface to electrical bias circuitry and a second electrical contact connecting a portion of the upper pole distant from the air bearing surface to the electrical bias circuitry;
an electrically insulating material layer is located between the portions of the main pole and the upper pole distal from the air bearing surface;
the electrically insulating material layer provides physical and electrical isolation between the portions of the main pole and the upper pole distal from the air bearing surface; and
the current flows between the main pole and the upper pole only through the record element.
16. The method of claim 14 , wherein:
the magnetic head comprises a microwave assisted magnetic recording head; and
an air bearing surface (ABS) of the magnetic recording head includes planar surfaces of the main pole, the spin torque oscillator stack, and the trailing magnetic shield which moves over the magnetic disk.
17. A magnetic head, comprising:
a main pole configured to serve as a first electrode;
an upper pole comprising a trailing magnetic shield configured to a serve as a second electrode; and
an electrically conductive, non-magnetic material record element located in a trailing gap between and in contact with the main pole and the trailing magnetic shield;
wherein the electrically conductive, non-magnetic material record element is not part of a spin torque oscillator stack,
wherein the main pole and the trailing magnetic shield are electrically shorted by the electrically conductive, non-magnetic material record element across the trailing gap between the main pole and the trailing magnetic shield such that an electrically conductive path is present between the main pole and the trailing magnetic shield through the record element,
wherein the magnetic head comprises a non-microwave assisted magnetic recording head which lacks a spin torque oscillator stack,
wherein the electrically conductive path is present through the electrically conductive, non-magnetic material record element between the first electrode and the second electrode, and
wherein the electrically conductive, non-magnetic material record element contacts a trailing sidewall of the main pole and a leading sidewall of the trailing magnetic shield in the trailing gap between the main pole and the trailing magnetic shield.
18. The magnetic head of claim 17 , wherein an air bearing surface (ABS) of the magnetic head includes planar surfaces of the main pole, the electrically conductive, non-magnetic material record element, and the trailing magnetic shield.
19. The magnetic head of claim 18 , further comprising an insulating material portion recessed from the ABS, the insulating material portion being disposed on the electrically conductive, non-magnetic material record element between and in contact with the main pole and the trailing magnetic shield.
20. The magnetic head of claim 19 , wherein a width of the insulating material portion is greater than a width of the electrically conductive, non-magnetic material record element.
21. The magnetic head of claim 17 , wherein the only electrically conductive path between the main pole and the upper pole is the electrically conductive path between the main pole and the trailing magnetic shield through the electrically conductive, non-magnetic material record element.
22. The magnetic head of claim 17 , wherein the electrically conductive, non-magnetic material record element comprises a copper, gold, platinum, ruthenium, chromium or tungsten layer.