Plasmon generator including a heat sink layer interposed between two portions formed of different metal materials

Patent metadata

Field	Value
Publication number	US-9754614-B1
Application number	US-201615244556-A
Country	US
Kind code	B1
Filing date	Aug 23, 2016
Priority date	Aug 23, 2016
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

A plasmon generator includes: a first portion formed of a first metal material and including a front end face configured to generate near-field light; a second portion formed of a second metal material and located at a distance from the front end face; and a heat sink layer formed of a third metal material, located at a distance from the front end face and interposed between the first portion and the second portion. The second metal material is lower in Vickers hardness and higher in thermal conductivity than the first metal material. The third metal material has a thermal conductivity higher than that of each of the first and second metal materials, and has a Vickers hardness lower than that of the first metal material and higher than that of the second metal material.

First claim

What is claimed is:

1. A plasmon generator having a front end face configured to generate near-field light from a surface plasmon, comprising:
a first portion formed of a first metal material and including the front end face;
a second portion formed of a second metal material and located at a distance from the front end face; and
a first heat sink layer formed of a third metal material, located at a distance from the front end face and interposed between the first portion and the second portion, wherein
the second metal material is lower in Vickers hardness and higher in thermal conductivity than the first metal material, and
the third metal material has a thermal conductivity higher than that of each of the first and second metal materials, and has a Vickers hardness lower than that of the first metal material and higher than that of the second metal material.

2. The plasmon generator according to claim 1 , wherein the second portion includes a plasmon exciting section configured to excite the surface plasmon thereon.

3. The plasmon generator according to claim 1 , wherein
the front end face has a first edge and a second edge opposite to each other in a first direction,
at least part of the first heat sink layer is located between a first imaginary plane and a second imaginary plane,
the first imaginary plane includes the first edge and is perpendicular to the first direction, and
the second imaginary plane includes the second edge and is perpendicular to the first direction.

4. The plasmon generator according to claim 1 , wherein the first metal material contains one of Rh, Ir, Ru and Pt.

5. The plasmon generator according to claim 4 , wherein the first metal material further contains one of Au, Cu, Ag and Al.

6. The plasmon generator according to claim 1 , wherein the second metal material is Au, and the third metal material is Cu.

7. The plasmon generator according to claim 1 , further comprising a second heat sink layer formed of a fourth metal material, located at a distance from the front end face and being in contact with the first portion,
wherein the fourth metal material is lower in Vickers hardness and higher in thermal conductivity than the first metal material.

8. The plasmon generator according to claim 7 , wherein
the front end face has a first edge and a second edge opposite to each other in a first direction,
at least part of the first heat sink layer and at least part of the second heat sink layer are located between a first imaginary plane and a second imaginary plane,
the first imaginary plane includes the first edge and is perpendicular to the first direction, and
the second imaginary plane includes the second edge and is perpendicular to the first direction.

9. The plasmon generator according to claim 7 , wherein the fourth metal material is Cu.

10. The plasmon generator according to claim 1 , wherein
the second portion has a contact surface in contact with the first heat sink layer,
the first heat sink layer includes a thickness-changing portion, and
in the thickness-changing portion, a thickness in a direction perpendicular to the contact surface decreases with decreasing distance to the front end face.

11. A thermally-assisted magnetic recording head comprising:
a medium facing surface configured to face a recording medium;
a main pole for producing a write magnetic field for use to write data on the recording medium;
a waveguide including a core and a cladding, the core allowing light to propagate therethrough, the cladding being provided around the core; and
the plasmon generator of claim 1 ,
wherein the front end face of the plasmon generator is located in the medium facing surface.

12. The thermally-assisted magnetic recording head according to claim 11 , wherein
the core has an evanescent light generating surface configured to generate evanescent light from the light propagating through the core,
the second portion includes a plasmon exciting section configured to excite the surface plasmon thereon, and
the plasmon generator is configured so that the surface plasmon is excited on the plasmon exciting section through coupling with the evanescent light, and then the surface plasmon propagates to the front end face.

13. The thermally-assisted magnetic recording head according to claim 11 , further comprising a heat sink interposed between the plasmon generator and the main pole.

14. The thermally-assisted magnetic recording head according to claim 13 , wherein
the heat sink has an inclined surface facing toward the medium facing surface,
the inclined surface has a first end closest to the plasmon generator, and a second end farthest from the plasmon generator,
the inclined surface is inclined with respect to the medium facing surface such that the second end is at a greater distance from the medium facing surface than is the first end, and
the main pole includes a portion located between the inclined surface and the medium facing surface.

15. A plasmon generator having a front end face configured to generate near-field light from a surface plasmon, comprising:
a first portion formed of a first metal material and including the front end face; and
a second portion formed of a second metal material and located at a distance from the front end face, wherein
the second metal material is lower in Vickers hardness and higher in thermal conductivity than the first metal material,
the first metal material contains one of Rh, Ir, Ru and Pt, and
the second metal material is Cu.

16. The plasmon generator according to claim 15 , wherein the first metal material further contains one of Au, Cu, Ag and Al.

17. The plasmon generator according to claim 15 , further comprising a first heat sink layer formed of Cu, the first heat sink layer being located at a distance from the front end face and interposed between the first portion and the second portion.

18. The plasmon generator according to claim 17 , wherein
the front end face has a first edge and a second edge opposite to each other in a first direction,
at least part of the first heat sink layer is located between a first imaginary plane and a second imaginary plane,
the first imaginary plane includes the first edge and is perpendicular to the first direction, and
the second imaginary plane includes the second edge and is perpendicular to the first direction.

19. The plasmon generator according to claim 17 , further comprising a second heat sink layer formed of Cu, the second heat sink layer being located at a distance from the front end face and in contact with the first portion.

20. The plasmon generator according to claim 19 , wherein
the front end face has a first edge and a second edge opposite to each other in a first direction,
at least part of the first heat sink layer and at least part of the second heat sink layer are located between a first imaginary plane and a second imaginary plane,
the first imaginary plane includes the first edge and is perpendicular to the first direction, and
the second imaginary plane includes the second edge and is perpendicular to the first direction.

21. A thermally-assisted magnetic recording head comprising:
a medium facing surface configured to face a recording medium;
a main pole for producing a write magnetic field for use to write data on the recording medium;
a waveguide including a core and a cladding, the core allowing light to propagate therethrough, the cladding being provided around the core; and
the plasmon ge

Assignees

• Sasaki Yoshitaka
• Ito Hiroyuki
• Ikegawa Yukinori
• Tanemura Shigeki
• Mamiya Hideo
• Tomita Seiichiro
• Headway Tech Inc

Inventors

• Sasaki Yoshitaka
• Ito Hiroyuki
• Ikegawa Yukinori
• Tanemura Shigeki
• Mamiya Hideo
• Tomita Seiichiro

Classifications

• G11B5/3929 Primary

  Disposition of magnetic thin films not used for directly coupling magnetic flux from the track to the MR film or for shielding · CPC title

• G02B5/008

  Surface plasmon devices (diffractive gratings with a pitch less than or comparable to the wavelength G02B5/1809; surface plasmons in integrated optics G02B6/1226; optical analysis of materials by means of surface plasmons G01N21/553) · 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

• G11B5/4866

  the arm comprising an optical waveguide, e.g. for thermally-assisted recording · CPC title

• G02B6/1226 Primary

  involving surface plasmon interaction · CPC title