Optically opaque overlay with periodic structures for a waveguide of a heat-assisted magnetic recording slider

Patent metadata

Field	Value
Publication number	US-9934801-B1
Application number	US-201715620550-A
Country	US
Kind code	B1
Filing date	Jun 12, 2017
Priority date	Jun 23, 2016
Publication date	Apr 3, 2018
Grant date	Apr 3, 2018

Abstract

An apparatus comprises a slider having an air bearing surface and is configured for heat-assisted magnetic recording. The slider comprises a write pole, a near-field transducer (NFT) proximate the write pole, and an optical waveguide configured to receive light from a light source and couple the light to the NFT. The optical waveguide comprises first and second opposing major surfaces and opposing first and second edges connected to the first and second major surfaces. An optically opaque overlay is disposed on or adjacent one or both of the first and second major surfaces of the optical waveguide. Periodic structures are disposed on a surface of the optically opaque overlay facing the waveguide. The periodic structures are configured to organize stray light emanating from the waveguide for absorption by the optically opaque overlay.

First claim

What is claimed is:

1. An apparatus, comprising:
a slider having an air bearing surface and configured for heat-assisted magnetic recording comprising:
a write pole;
a near-field transducer (NFT) proximate the write pole;
an optical waveguide configured to receive light from a light source and couple the light to the NFT, the optical waveguide comprising first and second opposing major surfaces and opposing first and second edges connected to the first and second major surfaces;
an optically opaque overlay disposed on or adjacent one or both of the first and second major surfaces of the optical waveguide; and
periodic structures disposed on a surface of the optically opaque overlay facing the waveguide, the periodic structures configured to organize stray light emanating from the waveguide for absorption by the optically opaque overlay.

2. The apparatus of claim 1 , wherein the optically opaque overlay is disposed on or adjacent the first and second major surfaces of the waveguide.

3. The apparatus of claim 1 , wherein:
the optically opaque overlay extends from at or near the air bearing surface of the slider into a body of the slider; and
the periodic structures are disposed on the overlay surface spaced away from the air bearing surface by at least about 20 μm.

4. The apparatus of claim 1 , wherein the periodic structures are configured as an omni-directional, omni-polarization absorber of stray light emanating from the waveguide.

5. The apparatus of claim 1 , wherein the periodic structures are formed from Cu.

6. The apparatus of claim 1 , wherein the periodic structures are formed from Cu and a layer of Cr over the Cu.

7. The apparatus of claim 1 , wherein the periodic structures have rounded edges.

8. The apparatus of claim 1 , wherein a gap between adjacent periodic structures ranges between about 1 and 2 μm.

9. The apparatus of claim 1 , wherein a gap between adjacent periodic structures is filled with a dielectric material.

10. The apparatus of claim 1 , wherein the periodic structures have a height of up to about 1 μm.

11. An apparatus, comprising:
a slider having an air bearing surface and configured for heat-assisted magnetic recording comprising:
a write pole;
a near-field transducer (NFT) proximate the write pole;
an optical waveguide configured to receive light from a light source and couple the light to the NFT, the optical waveguide comprising first and second opposing major surfaces and opposing first and second edges connected to the first and second major surfaces;
an optically opaque overlay disposed on or adjacent one or both of the first and second major surfaces of the optical waveguide;
a layer of dielectric material disposed on a surface of the optically opaque overlay facing the waveguide; and
periodic structures disposed on the layer of dielectric material, the periodic structures configured to organize stray light emanating from the waveguide for absorption by the optically opaque overlay.

12. The apparatus of claim 11 , wherein the optically opaque overlay is disposed on or adjacent the first and second major surfaces of the waveguide.

13. The apparatus of claim 11 , wherein:
the optically opaque overlay extends from at or near the air bearing surface of the slider into a body of the slider; and
the layer of dielectric material and periodic structures are disposed on the overlay surface spaced away from the air bearing surface by at least about 20 μm.

14. The apparatus of claim 11 , wherein the periodic structures are configured as an omni-directional, omni-polarization absorber of stray light emanating from the waveguide.

15. The apparatus of claim 11 , wherein the periodic structures are formed from Cu.

16. The apparatus of claim 11 , wherein the periodic structures are formed from Cu and a layer of Cr over the Cu.

17. The apparatus of claim 11 , wherein the periodic structures have rounded edges.

18. The apparatus of claim 11 , wherein a spacing between adjacent periodic structures ranges between about 1 and 2 μm.

19. The apparatus of claim 11 , wherein a gap between adjacent periodic structures is filled with a dielectric material.

20. The apparatus of claim 11 , wherein the periodic structures have a height of up to about 1 μm.

Assignees

• Seagate Technology Llc

Inventors

• Wessel James Gary
• Wang Chen
• Peng Chubing

Classifications

• G11B2005/0021

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

• G11B11/1051

  by modulating both the magnetic field and the light beam at the transducers · CPC title

• G11B7/126

  Circuits, methods or arrangements for laser control or stabilisation · CPC title

• G11B5/6088 Primary

  Optical waveguide in or on flying head · CPC title

• G11B11/10506

  by modulating only the light beam of the transducer · CPC title