Submount-integrated photodetector for monitoring a laser for a heat-assisted magnetic recording head

Patent metadata

Field	Value
Publication number	US-9245553-B2
Application number	US-201314089589-A
Country	US
Kind code	B2
Filing date	Nov 25, 2013
Priority date	Nov 25, 2013
Publication date	Jan 26, 2016
Grant date	Jan 26, 2016

Abstract

In a heat-assisted magnetic recording hard disk drive, a laser module includes a submount-integrated photodetector configured to receive optical energy from a laser by way of a head slider. The submount may be formed of a semiconductor material such as a crystalline silicon material, and the photodetector may be a photodiode that is integrally formed with the submount. A HAMR head slider may comprise a feedback waveguide configured to guide optical energy from the laser through the slider to a feedback photodiode at an interface of the submount and the slider, to detect the optical energy transmitted through the slider to the slider air bearing surface (ABS). A back facet photodiode may also be integrally formed with the submount and configured to receive back facet optical energy to detect the optical energy generated by the laser.

First claim

What is claimed is:

1. A laser module configured for use with a heat-assisted magnetic recording (HAMR) head slider, said laser module comprising:
a laser, and
a submount with which said laser is coupled, said submount comprising:
an aperture positioned on a face of said submount, and
an integrally-formed photodetector positioned to receive optical energy from said laser which is guided through said head slider and through said aperture.

2. The laser module of claim 1 , wherein said photodetector is a semiconductor photodiode integrally formed with said submount.

3. The laser module of claim 1 , wherein said submount is formed of a semiconductor material, and wherein said photodetector is a semiconductor photodiode integrally formed with said submount.

4. The laser module of claim 1 , wherein said submount is formed of a crystalline silicon material.

5. The laser module of claim 1 , wherein said photodetector is configured to receive optical energy from said laser by way of a first waveguide that is integrally formed with said head slider and configured to guide optical energy from said laser through said head slider to said photodetector.

6. The laser module of claim 1 , comprising:
a plurality of photodetector contact pads coupled with said submount and configured to transmit from said photodetector a feedback signal from which the optical energy transmitted through said head slider is computable.

7. The laser module of claim 1 , wherein said photodetector is a photodiode array.

8. The laser module of claim 1 , wherein said integrally-formed photodetector is a feedback photodetector, said laser module further comprising:
a back facet photodiode integrally-formed with said submount and configured to directly receive back facet optical energy from said laser from which the optical energy generated by said laser is computable.

9. A heat-assisted magnetic recording (HAMR) head slider assembly comprising:
a head slider comprising a magnetic write head configured to write to a magnetic-recording disk;
a laser module comprising:
a laser, and
a submount with which said laser is coupled, said submount comprising:
an aperture positioned on a face of said submount, and
an integrally-formed photodiode positioned to receive optical energy from said laser which is guided through a feedback waveguide configured to guide optical energy from said laser through said head slider and through said aperture to said photodiode; and

a HAMR waveguide configured to guide optical energy from said laser through said head slider to near said write head for generating heat in said disk.

10. The HAMR head slider assembly of claim 9 , wherein said submount is formed of a semiconductor material, and wherein said photodiode is a semiconductor photodiode integrally formed with said submount.

11. The HAMR head slider assembly of claim 9 , wherein said submount is formed of a crystalline silicon material.

12. The HAMR head slider assembly of claim 9 , comprising:
a plurality of photodiode contact pads coupled with said submount and configured to transmit from said photodiode a feedback signal from which the optical energy transmitted through said head slider via said feedback waveguide is computable.

13. The HAMR head slider assembly of claim 9 , wherein said integrally-formed photodiode is a feedback photodiode formed at an outer face of said submount, said assembly further comprising:
a back facet photodiode integrally-formed with said submount and configured to directly receive back facet optical energy from said laser from which the optical energy generated by said laser is computable.

14. The HAMR head slider assembly of claim 13 , wherein said feedback photodiode is formed near an interface of said submount and said head slider.

15. The HAMR head slider assembly of claim 9 , wherein said photodiode is a photodiode array.

16. A hard disk drive, comprising:
a magnetic-recording disk rotatably mounted on a spindle;
a heat-assisted magnetic recording (HAMR) head slider comprising:
a magnetic write head configured to write to said magnetic-recording disk;
a laser module comprising:
a laser, and
a submount with which said laser is coupled, said submount comprising:
an aperture positioned on a face of said submount, and
an integrally-formed photodetector positioned to receive optical energy from said laser which is guided through a feedback waveguide configured to guide optical energy from said laser through said head slider and through said aperture to said photodetector; and

a HAMR waveguide configured to guide optical energy from said laser through said head slider to near said magnetic write head for generating heat in said magnetic-recording disk; and

a voice coil motor configured to move said HAMR head slider to access portions of said magnetic-recording disk.

17. The hard disk drive of claim 16 , said HAMR head slider comprising:
said feedback waveguide configured to guide optical energy from said laser through said head slider to said photodetector positioned at an interface of said submount and said HAMR head slider.

18. The hard disk drive of claim 16 , wherein said submount is formed of a semiconductor material, and wherein said photodetector is a semiconductor photodiode integrally formed with said submount.

19. The hard disk drive of claim 16 , comprising:
a plurality of photodiode contact pads coupled with said submount and configured to transmit, from said photodiode to a controller, a feedback signal from which the optical energy transmitted through said head slider via said feedback waveguide is computable.

20. The hard disk drive of claim 16 , wherein said integrally-formed photodetector is a feedback photodiode formed at an interface of said submount and said HAMR head slider, said hard disk drive further comprising:
a back facet photodiode integrally-formed with said submount and configured to receive back facet optical energy from which the optical energy emitted by said laser is computable.

Assignees

• HGST Netherlands BV

Inventors

• Boone Jr Thomas Dudley
• Matsumoto Takuya
• Ren Shen

Classifications

• G11B5/4866 Primary

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

• G11B5/314

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

• G11B5/105

  Mounting of head within housing {or assembling of head and housing (G11B5/3103 takes precedence)} · CPC title

• G11B7/1384

  Fibre optics · CPC title