Systems and methods for monitoring the power of a light source utilized in energy-assisted magnetic recording

Patent metadata

Field	Value
Publication number	US-9431037-B2
Application number	US-201313797266-A
Country	US
Kind code	B2
Filing date	Mar 12, 2013
Priority date	Mar 12, 2013
Publication date	Aug 30, 2016
Grant date	Aug 30, 2016

Abstract

Aspects of the present invention relate to energy-assisted magnetic recording (EAMR), an EAMR assembly, and methods for fabricating the same. In several embodiments, an EAMR head includes a sub-mount on a slider that has a waveguide configured to receive light from a light source attached to a surface of the sub-mount. The waveguide receives the light at a top surface of the slider and routes the light to be near an air bearing surface (ABS) of the slider where energy of the light can be used to heat up a spot on a recording media disk that is proximate the ABS. The waveguide also routes a portion of the light back to the top surface of the slider where the light exits the waveguide and is detected by a light detector located along the surface of the sub-mount.

First claim

What is claimed is:

1. An energy-assisted magnetic recording (EAMR) head comprising:
a slider comprising a waveguide;
a sub-mount fixedly attached to the slider, the sub-mount comprising a light detector along a first sub-mount side of the sub-mount and spaced apart from the slider; and
a light source attached to the first sub-mount side, the light source configured to generate and transmit light to the waveguide,
wherein the light detector is configured to receive a first portion of the light transmitted to the waveguide.

2. The EAMR head of claim 1 , wherein the waveguide comprises a first end and a second end both located at a surface of the slider opposite an air bearing surface of the slider.

3. The EAMR head of claim 2 , wherein the waveguide is configured such that the light enters the waveguide at the first end and in a first direction, and the first portion of the light exits the waveguide at the second end and in a second direction that is substantially opposite to the first direction.

4. The EAMR head of claim 3 , wherein the waveguide is configured such that the first portion of the light exits the waveguide at an angle with respect to the surface of the slider.

5. The EAMR head of claim 4 , wherein the angle is substantially normal to the surface of the slider.

6. The EAMR head of claim 4 , wherein the angle is not normal to the surface of the slider.

7. The EAMR head of claim 1 , wherein the light source comprises a laser diode, and the light detector comprises a photodiode.

8. The EAMR head of claim 7 , wherein the photodiode is integrally formed in the sub-mount.

9. The EAMR head of claim 7 , wherein the photodiode is attached to the sub-mount.

10. The EAMR head of claim 7 , wherein the photodiode comprises an in-plane photodiode.

11. The EAMR head of claim 1 , wherein the waveguide comprises a first arm for transmitting the first portion of the light to the light detector.

12. The EAMR head of claim 11 , wherein the first arm extends to a surface of the slider opposite an air bearing surface of the slider.

13. The EAMR head of claim 11 , wherein a section of the first arm gradually increases in width in a light propagating direction toward the light detector.

14. The EAMR head of claim 11 ,
wherein the waveguide further comprises a second arm for receiving the light from the light source, and the first arm is configured to receive the first portion of the light from the second arm, and
wherein the second arm is configured to transmit a second portion of the light to a storage medium located proximate an air bearing surface of the slider.

15. The EAMR head of claim 14 , further comprising a near-field transducer located proximate the air bearing surface of the slider and optically coupled with the second arm of the waveguide for transferring energy of the second portion of the light to a location on the storage medium.

16. The EAMR head of claim 14 , wherein the waveguide further comprises a third arm for transmitting a third portion of the light to a second light detector.

17. The EAMR head of claim 16 , wherein the third arm extends to a trailing edge side of the slider.

18. The EAMR head of claim 17 , wherein the third arm is configured to emit the third portion of the light from the trailing edge side of the slider.

19. The EAMR head of claim 16 , wherein the first arm and the third arm are substantially symmetrical in shape.

20. The EAMR head of claim 16 , wherein second arm splits into two branches that are optically coupled to the first arm and the third arm, respectively.

21. The EAMR head of claim 16 ,
wherein the first arm and the third arm are spaced apart from the second arm; and
wherein the first arm and the third arm are optically coupled with the second arm.

22. The EAMR head of claim 1 , wherein the waveguide comprises one selected from the group consisting of a channel waveguide, a planar waveguide, and a combination thereof.

23. The EAMR head of claim 1 , wherein the waveguide is configured to output the first portion of the light as a light beam with a divergent portion that extends toward the light detector.

24. The EAMR head of claim 1 , wherein the light source has a first light source side attached to the first sub-mount side and a second light source side opposite the first light source side, and the light source is configured to output the light at the first light source side.

25. The EAMR head of claim 1 , wherein the light source has a first light source side attached to the first sub-mount side and a second light source side opposite the first light source side, and the light source is configured to output the light at the second light source side.

26. The EAMR head of claim 1 , further comprising a plurality of metal traces on the sub-mount and electrically coupled to the light source and light detector, respectively.

27. The EAMR head of claim 1 , wherein the light source and the light detector extend side-by-side in a height direction of the sub-mount, wherein the height direction is normal to an air bearing surface of the slider.

28. The EAMR head of claim 1 , wherein the sub-mount and the light source have about the same height in a direction normal to an air bearing surface of the slider.

29. The EAMR head of claim 1 , wherein the first sub-mount side extends in a direction substantially normal to an air bearing surface of the slider.

30. The EAMR head of claim 1 , wherein the sub-mount is directly attached to the slider.

31. The EAMR head of claim 1 , wherein the light detector is configured to receive light emitted from the waveguide.

32. A method of fabricating an energy-assisted magnetic recording (EAMR) head, the method comprising:
providing a slider comprising a waveguide;
attaching a light source at a first sub-mount side of a sub-mount, the light source configured to generate and transmit light to the waveguide; and
fixedly attaching the sub-mount to the slider, the sub-mount comprising a light detector along the first sub-mount side of the sub-mount and spaced apart from the slider,
wherein the light detector is configured to receive a first portion of the light transmitted to the waveguide.

33. The method of claim 32 , wherein the waveguide comprises a first end and a second end both located at a surface of the slider opposite an air bearing surface of the slider.

34. The method of claim 33 , wherein the waveguide is configured such that the light enters the waveguide at the first end in a first direction, and the first portion of the light exits the waveguide at the second end in a second direction that is opposite to the first direction.

35. The method of claim 34 , wherein the waveguide is configured such that the first portion of the light exits the waveguide at an angle with respect to the surface of the slider.

36. The method of claim 35 , wherein the angle is substantially normal to the surface of the slider.

37. The method of claim 35 , wherein the angle is not normal to the surface of the slider.

38. The method of claim 32 , wherein the light source comprises a laser diode, and the light detector comprises a photodiode.

39. The method of claim 38 , wherein t

Assignees

• Western Digital (Fremont) Llc
• Western Digitatl (Fremont) Llc

Inventors

• Kozlovsky William J
• Wang Lei
• Goulakov Arkadi B
• Do Khiem Ba

Classifications

• Y10T29/49032

  Fabricating head structure or component thereof · CPC title

• G11B5/6088

  Optical waveguide in or on flying head · CPC title

• G11B5/127

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

• G11B5/1475

  Assembling or shaping of elements (G11B5/153 takes 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