Thermally-assisted magnetic recording head including a main pole and a plasmon generator

Patent metadata

Field	Value
Publication number	US-9812156-B2
Application number	US-201514600460-A
Country	US
Kind code	B2
Filing date	Jan 20, 2015
Priority date	Jan 20, 2015
Publication date	Nov 7, 2017
Grant date	Nov 7, 2017

Abstract

A thermally-assisted magnetic recording head includes a main pole and a plasmon generator. The main pole has a front end face located in the medium facing surface. The plasmon generator has a near-field light generating surface located in the medium facing surface. The front end face of the main pole includes a first end face portion and a second end face portion. The second end face portion is located farther from the near-field light generating surface than is the first end face portion, and is greater than the first end face portion in width in the track width direction. The first end face portion and the near-field light generating surface are equal in width.

First claim

What is claimed is:

1. A thermally-assisted magnetic recording head comprising:
a medium facing surface configured to face a recording medium;
a coil for producing a magnetic field corresponding to data to be written on the recording medium;
a main pole having a front end face located in the medium facing surface;
a waveguide including a core and a cladding, the core allowing light to propagate therethrough, the cladding being provided around the core;
a plasmon generator having a near-field light generating surface located in the medium facing surface;
a shield formed of a magnetic material and having an end face located in the medium facing surface; and
a return path section formed of a magnetic material, connecting the main pole and the shield to each other and passing a magnetic flux corresponding to the magnetic field produced by the coil, wherein
the main pole is configured to pass a magnetic flux corresponding to the magnetic field produced by the coil, and to produce from the front end face a write magnetic field for writing the data on the recording medium,
the plasmon generator is configured to excite a surface plasmon on the plasmon generator based on the light propagating through the core, and to generate near-field light from the near-field light generating surface based on the surface plasmon,
the front end face of the main pole and the near-field light generating surface are at locations different from each other in a direction of travel of the recording medium,
the front end face of the main pole includes a first end face portion, and a second end face portion contiguous with the first end face portion,
the second end face portion is located farther from the near-field light generating surface than is the first end face portion, and is greater than the first end face portion in width in a track width direction,
the first end face portion has a first edge and a second edge opposite to each other in the track width direction,
the near-field light generating surface has a third edge and a fourth edge opposite to each other in the track width direction, and a fifth edge and a sixth edge opposite to each other in the direction of travel of the recording medium,
an entire shape of the near-field light generating surface defined by the third to sixth edges is rectangular,
the first edge and the third edge are located on a first imaginary straight line,
the second edge and the fourth edge are located on a second imaginary straight line parallel to the first imaginary straight line,
the first edge and the second edge are straight lines parallel to each other in a plane of the front end face,
the near-field light generating surface is located between the front end face of the main pole and at least part of the end face of the shield,
the return path section includes a first yoke portion, a second yoke portion, a first columnar portion, a second columnar portion, and a third columnar portion,
the first yoke portion, the second yoke portion and the first columnar portion are located on a same side in the direction of travel of the recording medium relative to the core,
the first columnar portion is located away from the medium facing surface and has a first end and a second end opposite to each other in the direction of travel of the recording medium,
the second and third columnar portions are located closer to the medium facing surface than is the first columnar portion,
the first yoke portion connects the main pole to the first end of the first columnar portion,
the second columnar portion and the third columnar portion are located on opposite sides of the plasmon generator in the track width direction, and are connected to the shield,
the second yoke portion is connected to the second end of the first columnar portion, and is connected to the shield via the second and third columnar portions, and
the coil is wound around the first columnar portion.

2. The thermally-assisted magnetic recording head according to claim 1 , further comprising a dielectric layer provided between the main pole and the plasmon generator.

3. The thermally-assisted magnetic recording head according to claim 1 , wherein
the core has an evanescent light generating surface for generating evanescent light based on the light propagating through the core,
the plasmon generator has a plasmon exciting section located at a predetermined distance from the evanescent light generating surface and facing the evanescent light generating surface, and
in the plasmon generator, the surface plasmon is excited on the plasmon exciting section through coupling with the evanescent light generated by the evanescent light generating surface, the surface plasmon propagates to the near-field light generating surface, and the near-field light generating surface generates near-field light based on the surface plasmon.

4. The thermally-assisted magnetic recording head according to claim 1 , wherein the front end face of the main pole is located on a front side in the direction of travel of the recording medium relative to the near-field light generating surface.

5. The thermally-assisted magnetic recording head according to claim 1 , wherein
the main pole includes a first layer, and a second layer stacked on the first layer,
the first layer has the first end face portion, and
the second layer has the second end face portion.

6. The thermally-assisted magnetic recording head according to claim 5 , wherein
the first layer further has a first rear end face portion farthest from the medium facing surface,
the second layer further has a second rear end face portion farthest from the medium facing surface, and
the first rear end face portion and the second rear end face portion are located at a same distance from the medium facing surface.

7. The thermally-assisted magnetic recording head according to claim 6 , further comprising a heat sink having an outer surface, wherein
the plasmon generator has a top surface including a first region and a second region, the second region being located farther from the medium facing surface than the first region,
the first layer of the main pole has a bottom surface opposed to the first region of the top surface of the plasmon generator, and a first side surface and a second side surface located at opposite ends of the first layer in the track width direction,
the second layer of the main pole has a third side surface and a fourth side surface located at opposite ends of the second layer in the track width direction, and
the outer surface of the heat sink includes: a first portion opposed to the second region of the top surface of the plasmon generator; a second portion opposed to the first rear end face portion; a third portion opposed to the second rear end face portion; a fourth portion opposed to at least part of the third side surface; and a fifth portion opposed to at least part of the fourth side surface.

8. The thermally-assisted magnetic recording head according to claim 7 , wherein the outer surface of the heat sink further includes a sixth portion opposed to at least part of the first side surface, and a seventh portion opposed to at least part of the second side surface.

9. The thermally-assisted magnetic recording head according to claim 1 , wherein the end face of the shield includes a first side shield end face and a second side shield end face located on opposite sides of the first end face portion of the front end face of the main pole in the track width direction.

10. A method of manufacturing the thermally-assisted magnetic recording head of claim 1 , comprising the steps of:
forming the waveguide;
forming the plasmon generator and the main pole; and
forming

Assignees

• Sasaki Yoshitaka
• Ito Hiroyuki
• Tanemura Shigeki
• Mamiya Hideo
• Araki Hironori
• Tomita Seiichiro
• Headway Tech Inc

Inventors

• Sasaki Yoshitaka
• Ito Hiroyuki
• Tanemura Shigeki
• Mamiya Hideo
• Araki Hironori
• Tomita Seiichiro

Classifications

• G11B5/012

  Recording on, or reproducing or erasing from, magnetic disks (G11B17/00, G11B19/00 take precedence) · CPC title

• G11B5/314 Primary

  where the layers are extra layers normally not provided in the transducing structure, e.g. optical layers (G11B5/3196 takes precedence) · CPC title

• G11B2005/0021

  Thermally assisted recording using an auxiliary energy source for heating the recording layer locally to assist the magnetization reversal · CPC title

• G11B5/127

  Structure or manufacture of heads, e.g. inductive · CPC title

• G11B5/1272

  Assembling or shaping of elements (G11B5/1278 takes precedence) · CPC title