Parallel optical interconnect

• US 5,631,988 A
• Filed: 06/21/1996
• Issued: 05/20/1997
• Est. Priority Date: 05/24/1993
• Status: Expired due to Term

• Current Assignee: Optical Communication Products Incorporated (KOCH Industries Incorporated)
• Original Assignee: Vixel Corporation (Broadcom, Inc.)
• Inventors: Uchida, Toshi K., Swirhun, Stanley E.
• Primary Examiner(s): Ullah, Akm E.
• Application Number:
  US08/667,367
• Time in Patent Office: 333 Days
• Field of Search: 385/15, 385/17, 385/78, 385/88, 385/92
• US Class Current: 385/89
• CPC Class Codes: G02B 6/245 Removing protective coverings of light guides before coupling
• CPC Class Codes: G02B 6/42 Coupling light guides with opto-electronic elements
• CPC Class Codes: G02B 6/4202 for coupling an active element with fibres without intermediate optical elements, e.g. fibres with plane ends, fibres with shaped ends, bundles
• CPC Class Codes: G02B 6/421 the intermediate optical component consisting of a short length of fibre, e.g. fibre stub
• CPC Class Codes: G02B 6/4224 using visual alignment markings, e.g. index methods
• CPC Class Codes: G02B 6/4231 with intermediate elements, e.g. rods and balls, between the elements
• CPC Class Codes: G02B 6/4232 using the surface tension of fluid solder to align the elements, e.g. solder bump techniques flip-chip mounting techniques in assembly of semiconductor devices H01L24/81
• CPC Class Codes: G02B 6/4246 Bidirectionally operating package structures
• CPC Class Codes: G02B 6/4249 comprising arrays of active devices and fibres
• CPC Class Codes: G02B 6/43 Arrangements comprising a plurality of opto-electronic elements and associated optical interconnections

Abstract

An optical interconnect is disclosed that couples multiple optical fibers to an array of optoelectronic devices. The interconnect includes a multiple optical fiber connector and an optoelectronic board. The multiple fiber connector can be mechanically attached to or detached from the board.

Claims

1. An optical interconnect comprising:

a multiple optical fiber connector comprising;

a holder having a first planar surface,

a plurality of optical fibers attached to the holder, each fiber having a first end abutting the first surface so as to expose the first end for receiving or transmitting optical radiation, the first ends of the fibers forming a fiber array having a first pattern, and

guiding means disposed in said holder at predetermined positions with respect to the fiber array; and

an optoelectronic board comprising;

an optoelectronic device array monolithically formed on a semiconductor chip, said optoelectronic device array having substantially the same pattern as the first pattern of said fiber array, and

aligning means formed on said chip, said aligning means being disposed at substantially the same predetermined positions with respect to said array of optoelectronic devices as the positions of the guiding means relative to said fiber array, and

said aligning means receiving said guiding means so as to mechanically align said optoelectronic device array with said optical fiber array, whereby each optoelectronic device is aligned to an optical fiber, said optoelectronic device emitting optical radiation into said fiber array or receiving optical radiation from said fiber array.

2. The interconnect of claim 1 wherein said guiding means comprises two guiding pins mounted in the holder, said pins extending through said first planar surface of the holder, and said aligning means comprises two aligning holes, the fiber array being aligned to the optoelectronic device array by aligning and engaging said guiding pins with said aligning holes.

3. The interconnect of claim 2 wherein said fiber array is disposed between the two guiding pins.

4. The interconnect of claim 1 wherein said guiding means comprises two guiding pins mounted in the holder, said pins extending through said first surface of the holder in a direction perpendicular to said first surface, and said aligning means including two aligning holes, said fiber array being aligned to said optoelectronic device array by aligning and engaging said guiding pins with said aligning holes.

5. The interconnect of claim 4 wherein said fiber array are disposed between said two guiding pins.

6. The interconnect of claim 1 wherein the fibers form a one-dimensional array.

7. The interconnect of claim 1 wherein the fibers form a two-dimensional array.

8. The interconnect of claim 6 wherein the optoelectronic device array comprises a one-dimensional array of vertical cavity surface emitting lasers, each laser being axially aligned to a fiber and the fibers receiving optical radiation emitted by the lasers.

9. The interconnect of claim 8 further comprising a first electronic circuit means interconnected to said array of lasers for driving and modulating said lasers.

10. The interconnect of claim 8 wherein each of the optical fibers is a plastic optical fiber.

11. The interconnect of claim 8 wherein each of the optical fibers is a single-mode optical fiber.

12. The interconnect of claim 8 wherein each of the optical fibers is a multi-mode optical fiber.

13. The interconnect of claim 12 wherein each multi-mode optical fiber has a diameter of approximately 62.5 μ

m.

14. The interconnect of claim 13 wherein each of the vertical cavity surface emitting lasers has a diameter of approximately 20 μ

m.

15. The interconnect of claim 6 wherein the array of optoelectronic devices comprises an one-dimensional array of photo-detectors, each photo-detector being axially aligned to an end of a fiber, and the detectors receiving optical radiation emitted by the lasers.

16. The interconnect of claim 15 wherein the photo-detectors are Schottky-barrier photo-detectors.

17. The interconnect of claim 15 further comprising a second electronic means for receiving an electronic signal from the photo-detectors.

18. The interconnect of claim 16 wherein each of the optical fibers is a multi-mode optical fiber.

19. The interconnect of claim 18 wherein each multi-mode optical fiber has a diameter of approximately 62.5 μ

m.

20. The interconnect of claim 19 wherein each photo-detector has a diameter of approximately 100 μ

m.

42. The interconnect of claim 6 wherein the optoelectronic device array comprises a one-dimensional array of super luminescence diodes, each diode being axially aligned to a fiber and the fibers receiving optical radiation emitted by the diodes.

21. A method for interconnecting an optical connector to an optoelectronic board comprising the steps of:

providing a multiple optical fiber connector, said connector comprising;

a holder having at least one planar surface,

a plurality of optical fibers attached to the holder, each fiber having a first end abutting the first surface so as to expose the first end for receiving or transmitting optical radiation, the first ends of the fibers forming a fiber array having a first pattern, and

guiding means disposed in said holder at predetermined positions with respect to the fiber array;

providing an optoelectronic board, said board comprising;

an array of optoelectronic devices monolithically formed on a semiconductor chip, said optoelectronic devices having substantially the same pattern as the first pattern of said fiber array, and

aligning means formed on the chip, said aligning means being disposed at substantially the same predetermined positions with respect to said array of optoelectronic devices as the position of the guiding means relative to said fiber array; and

aligning and engaging said guiding means of said connector with said aligning means of said board so as to mechanically align said array of optoelectronic devices with said array of the optical fiber, whereby each optoelectronic device is aligned to an end of the fiber, said array of optoelectronic devices emitting optical radiation into said fiber array or receiving optical radiation from the fiber array.

22. An optical interconnect comprising:

an optical fiber having a coupling end, said optical fiber comprising a core and a cladding layer surrounding said core, said core at the coupling end being recessed so as to form a structure having a rim, the rim comprising substantially the cladding layer; and

a vertical cavity surface emitting laser comprising;

a semiconductor substrate,

a first mirror formed on said substrate, and a second mirror disposed above and parallel to the first mirror and forming with said first mirror an optical cavity that is perpendicular to the substrate, the first and second mirrors being distributed Bragg reflectors comprising a plurality of layers formed one on top of the other, and

an active region surrounded by first and second spacers disposed between said mirror,

the uppermost layers of said second mirror forming a mesa having a diameter less than an inner diameter of the rim,

said mesa engaging said rimmed structure so as to place a substantial portion of said mesa inside the rim, and

said laser emitting optical radiation that is substantially coupled into said optical fiber.

23. The interconnect of claim 22 further comprising holding means for maintaining the relative positions between the coupling end of said optical fiber and said laser.

24. The interconnect of claim 23 wherein said holding means comprises epoxy applied to the exterior of the coupling end and the laser.

25. The interconnect of claim 22 wherein said laser further comprises a contact surrounding the mesa and formed on the layers of said second mirror that is close to the active region.

26. The interconnect of claim 22 wherein said fiber is a single mode fiber.

27. The interconnect of claim 22 wherein said fiber is a multi-mode fiber.

28. The interconnect of claim 22 wherein said mesa has a thickness of 1 to 3 μ

m.

29. The interconnect of claim 22 wherein said laser further comprises an annular implanted current confinement region surrounding the active region.

30. A parallel optical interconnect comprising:

an optical connector comprising;

a holder having a first planar surface,

a plurality of optical fibers attached to said holder, each fiber having a coupling end abutting the first surface so as to expose the coupling end for receiving or transmitting optical radiation,

each said optical fiber comprising a core and a cladding layer surrounding said core, said core at the coupling end being recessed so as to form a structure having a rim, the rim comprising substantially the cladding layer,

said coupling end of the fibers forming a fiber array having a first pattern; and

an array of vertical cavity surface emitting lasers monolithically formed on a semiconductor chip, said array having substantially the same pattern as said fiber array, and each laser comprising;

a first mirror formed on said chip, and a second mirror disposed above and parallel to the first mirror and forming with said first mirror an optical cavity that is perpendicular to the chip, the first and second mirrors being distributed Bragg reflectors comprising a plurality of layers formed one on top of the other, and

an active region surrounded by first and second spacers disposed between said mirror,

the uppermost layers of said second mirror forming a mesa having a diameter less than an inner diameter of the rim,

each mesa being aligned to and engaging an optical fiber so as to place a substantial portion of said mesa inside the rim of a fiber, and

each laser emitting optical radiation that is substantially coupled into an optical fiber.

31. The interconnect of claim 30 further comprising holding means for maintaining the relative positions between the coupling ends of said fiber array and said lasers.

32. The interconnect of claim 31 wherein said holding means comprises epoxy applied to the exterior of the coupling ends and the lasers.

33. The interconnect of claim 31 wherein each laser further comprises a contact surrounding the mesa and formed on the layers of said second mirror that is close to the active region.

34. The interconnect of claim 31 wherein each fiber is a single mode fiber.

35. The interconnect of claim 31 wherein each fiber is a multi-mode fiber.

36. The interconnect of claim 31 wherein each mesa has a thickness of 1 to 3 μ

m.

37. The interconnect of claim 31 wherein each laser further comprises an annular implanted current confinement region surrounding the active region.

38. The interconnect of claim 31 further comprising guiding means disposed in said holder, and aligning means formed on said chip, said aligning means receiving said guiding means so as to mechanically align said array of lasers to said fiber array.

39. The interconnect of claim 38 wherein said guiding means comprises two guiding pins mounted in the holder, said pins extending through said first surface of the holder, and said aligning means including two aligning holes in said chip, the fiber array being aligned to the array of lasers by aligning and engaging said guiding pins with said aligning holes.

40. The interconnect of claim 31 wherein said fiber array and said array of lasers are two-dimensional arrays having substantially the same pattern.

41. The interconnect of claim 31 wherein said fiber array and said array of lasers are one-dimensional arrays having substantially the same pattern.

43. The interconnect of claim 33 wherein each laser further comprises a substrate contact disposed below the substrate.