METHOD AND SYSTEM FOR A LIGHT SOURCE ASSEMBLY SUPPORTING DIRECT COUPLING TO AN INTEGRATED CIRCUIT

• US 20100006784A1
• Filed: 07/09/2009
• Published: 01/14/2010
• Est. Priority Date: 07/09/2008
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Luxtera Incorporated (Cisco Systems, Inc.)
• Inventors: Mack, Michael, Peterson, Mark, Koumans, Roger, Narasimha, Adithyaram, De Dobbelaere, Peter, Gloeckner, Steffen
• Granted Patent: US 8,168,939 B2
• Time in Patent Office: Days
• US Class Current: 250/551
• CPC Class Codes: G02B 26/105 with one or more pivoting mirrors or galvano-mirrors G02B26/101 takes precedence
• CPC Class Codes: G02B 6/305 and having an integrated mode-size expanding section, e.g. tapered waveguide
• CPC Class Codes: G02B 6/32 having lens focusing means positioned between opposed fibre ends with lens being an integral part of the single fibre end G02B6/262
• CPC Class Codes: G02B 6/34 utilising prism or grating G02B6/293 takes precedence
• CPC Class Codes: G02B 6/4208 using non-reciprocal elements or birefringent plates, i.e. quasi-isolators optical isolators per se G02F1/093, G02F1/0955
• CPC Class Codes: G02B 6/4214 the intermediate optical element having redirecting reflective means, e.g. mirrors, prisms for deflecting the radiation from horizontal to down- or upward direction toward a device G02B6/4246 takes precedence
• CPC Class Codes: G02B 6/43 Arrangements comprising a plurality of opto-electronic elements and associated optical interconnections
• CPC Class Codes: H01S 5/005 Optical components external to the laser cavity, specially adapted therefor, e.g. for homogenisation or merging of the beams or for manipulating laser pulses, e.g. pulse shaping H01S5/026, H01S5/18388 take precedence
• CPC Class Codes: H01S 5/0064 Anti-reflection components, e.g. optical isolators
• CPC Class Codes: H01S 5/187 using Bragg reflection
• CPC Class Codes: H04B 10/503 Laser transmitters

Abstract

Methods and systems for a light source assembly supporting direct coupling to a photonically enabled complementary metal-oxide semiconductor (CMOS) chip are disclosed. The assembly may include a laser, a microlens, a turning mirror, reciprocal and/or non-reciprocal polarization rotators, and an optical bench. The laser may generate an optical signal that may be focused utilizing the microlens. The optical signal may be reflected at an angle defined by the turning mirror, and may be transmitted out of the light source assembly to one or more grating couplers in the chip. The laser may include a feedback insensitive laser. The light source assembly may include two electro-thermal interfaces between the optical bench, the laser, and a lid affixed to the optical bench. The turning mirror may be integrated in a lid affixed to the optical bench or may be integrated in the optical bench.

Claims

1. A system for processing signals, the system comprising:

a light source assembly affixed to a photonically enabled complementary metal-oxide semiconductor (CMOS) chip, said light source assembly comprising a laser, a microlens, a reciprocal polarization rotator, a non-reciprocal polarization rotator, a turning mirror, and an optical bench, said light source assembly being operable to;

generate an optical signal utilizing said laser;

focus said optical signal utilizing said microlens;

rotate a polarization of said optical signal utilizing said reciprocal polarization rotator;

reflect said optical signal at an angle defined by said turning mirror;

transmit said reflected optical signal out of said light source assembly to one or more grating couplers in said photonically enabled CMOS chip; and

reduce optical feedback to said laser from an optical signal returned from said photonically enabled CMOS chip utilizing said non-reciprocal polarization rotator.

2. The system according to claim 1, wherein said non-reciprocal polarization rotator comprises a faraday rotator.

3. The system according to claim 1, wherein said non-reciprocal polarization rotator comprises a latching faraday rotator.

4. The system according to claim 1, wherein said reciprocal polarization rotator comprises a half-wave plate.

5. The system according to claim 4, wherein said half-wave plate comprises a dielectric stack comprising one or more birefringent materials affixed to said optical bench.

6. The system according to claim 1, wherein said turning mirror is integrated in said optical bench.

7. The system according to claim 1, wherein said turning mirror is integrated in a lid affixed to said optical bench.

8. The system according to claim 1, wherein said light source assembly comprises two electro-thermal interfaces between said optical bench, said laser, and a lid affixed to said optical bench.

9. The system according to claim 1, wherein said microlens comprises a ball lens.

10. The system according to claim 1, wherein said laser comprises a semiconductor laser diode.

11. The system according to claim 1, wherein said laser comprises an edge emitting laser diode.

12. The system according to claim 1, wherein said optical bench functions as a mechanical support structure for one or more optical components of said light source assembly and said reflected optical signal passes through said optical bench.

13. The system according to claim 1, wherein said optical bench comprises silicon.

14. The system according to claim 1, wherein one or more interposers are applied between said light source assembly and said CMOS chip.

15. The system according to claim 14, wherein said one or more interposers comprise metal pads integrated into said CMOS chip.

16. The system according to claim 14, wherein said one or more interposers comprise one or more polymer pads deposited on said CMOS chip.

17. A system for processing signals, the system comprising:

a light source assembly affixed to a photonically enabled complementary metal-oxide semiconductor (CMOS) chip, said light source assembly comprising a laser, a microlens, a non-reciprocal polarization rotator, a turning mirror, and an optical bench, said light source assembly being operable to;

generate an optical signal utilizing said laser;

focus said generated optical signal utilizing said microlens;

reflect said optical signal at an angle defined by said turning mirror; and

transmit said reflected optical signal out of said light source assembly to one or more grating couplers in said photonically enabled CMOS chip; and

reduce optical feedback to said laser from an optical signal returned from said photonically enabled CMOS chip utilizing said non-reciprocal polarization rotator.

18. The system according to claim 17, wherein said non-reciprocal polarization rotator comprises a faraday rotator.

19. The system according to claim 17, wherein said non-reciprocal polarization rotator comprises a latching faraday rotator.

20. The system according to claim 17, wherein said light source assembly comprises two electro-thermal interfaces between said optical bench, said laser, and a lid affixed to said optical bench.

21. The system according to claim 17, wherein said turning mirror is integrated in said optical bench.

22. The system according to claim 17, wherein said turning mirror is integrated in a lid affixed to said optical bench.

23. The system according to claim 17, wherein said microlens comprises a ball lens.

24. The system according to claim 17, wherein said laser comprises a semiconductor laser diode.

25. The system according to claim 17, wherein said laser comprises an edge emitting laser diode.

26. The system according to claim 17, wherein said optical bench functions as a mechanical support structure for one or more optical components of said light source assembly and said reflected optical signal passes through said optical bench.

27. The system according to claim 17, wherein said optical bench comprises silicon.

28. The system according to claim 17, wherein one or more interposers are integrated between said light source assembly and said CMOS chip.

29. The system according to claim 28, wherein said one or more interposers comprise metal pads integrated into said CMOS chip.

30. The system according to claim 28, wherein said one or more interposers comprise one or more polymer pads deposited on said CMOS chip.

31. A system for processing signals, the system comprising:

a light source assembly affixed to a photonically enabled complementary metal-oxide semiconductor (CMOS) chip, said light source assembly comprising a laser, a microlens, a turning mirror, a reciprocal polarization rotator, and an optical bench, said light source assembly being operable to;

generate an optical signal utilizing said laser;

focus said generated optical signal utilizing said microlens;

rotate a polarization of said optical signal utilizing said reciprocal polarization rotator;

reflect said optical signal at an angle defined by said turning mirror;

transmit said reflected optical signal out of said light source assembly to one or more grating couplers in said photonically enabled CMOS chip.

32. The system according to claim 31, wherein said laser comprises a semiconductor laser diode.

33. The system according to claim 31, wherein said laser comprises an edge-emitting laser diode.

34. The system according to claim 31, wherein said reciprocal polarization rotator comprises a half-wave plate.

35. The system according to claim 34, wherein said half-wave plate comprises a dielectric stack comprising one or more birefringent materials affixed to said optical bench.

36. The system according to claim 31, wherein said light source assembly comprises two electro-thermal interfaces between said optical bench, said laser, and a lid affixed to said optical bench.

37. The system according to claim 31, wherein said turning mirror is integrated in a lid affixed to said optical bench.

38. The system according to claim 31, wherein said turning mirror is integrated in said optical bench.

39. The system according to claim 31, wherein said microlens comprises a ball lens.

40. The system according to claim 31, wherein said optical bench functions as a mechanical support structure for one or more optical components of said light source assembly and said reflected optical signal passes through said optical bench.

41. The system according to claim 31, wherein said optical bench comprises silicon.

42. The system according to claim 31, wherein one or more interposers are integrated between said light source assembly and said CMOS chip.

43. The system according to claim 42, wherein said one or more interposers comprise metal pads integrated into said CMOS chip.

44. The system according to claim 42, wherein said one or more interposers comprise one or more polymer pads deposited on said CMOS chip.

45. A system for processing signals, the system comprising:

a light source assembly affixed to a photonically enabled complementary metal-oxide semiconductor (CMOS) chip, said light source assembly comprising a laser, a microlens, a turning mirror, and an optical bench, said light source assembly being operable to;

generate an optical signal utilizing said laser;

focus said generated optical signal utilizing said microlens;

reflect said optical signal at an angle defined by said turning mirror; and

transmit said reflected optical signal out of said light source assembly to one or more grating couplers in said photonically enabled CMOS chip.

46. The system according to claim 45, wherein said laser comprises semiconductor laser diode.

47. The system according to claim 45, wherein said laser comprises an edge-emitting laser diode.

48. The system according to claim 45, wherein said laser comprises a feedback insensitive laser diode.

49. The system according to claim 45, wherein said light source assembly comprises two electro-thermal interfaces between said optical bench, said laser, and a lid affixed to said optical bench.

50. The system according to claim 45, wherein said turning mirror is integrated in a lid affixed to said optical bench.

51. The system according to claim 45, wherein said turning mirror is integrated in said optical bench.

52. The system according to claim 45, wherein said microlens comprises a ball lens.

53. The system according to claim 45, wherein said optical bench functions as a mechanical support structure for one or more optical components of said light source assembly and said reflected optical signal passes through said optical bench.

54. The system according to claim 45, wherein said optical bench comprises silicon.

55. The system according to claim 45, wherein one or more interposers are integrated between said light source assembly and said CMOS chip.

56. The system according to claim 55, wherein said one or more interposers comprise metal pads integrated into said CMOS chip.

57. The system according to claim 55, wherein said one or more interposers comprise one or more polymer pads deposited on said CMOS chip.