Apparatus providing simplified alignment of optical fiber in photonic integrated circuits

• US 9,341,787 B2
• Filed: 01/02/2013
• Issued: 05/17/2016
• Est. Priority Date: 01/02/2013
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Sandhu, Gurtej, Meade, Roy, Bi, Lei, Smythe, John
• Primary Examiner(s): Lepisto, Ryan
• Assistant Examiner(s): Chiem, Erin
• Application Number:
  US13/732,557
• Publication Number:
  US 20140185983A1
• Time in Patent Office: 1,231 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: G02B 6/30 for use between fibre and thin-film device
• 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 6/4204 the coupling comprising intermediate optical elements, e.g. lenses, holograms encapsulated active devices H01S5/02208, H01L33/52
• CPC Class Codes: G02B 6/4206 Optical features G02B6/4207, G02B6/421 take precedence
• CPC Class Codes: G02B 6/4225 by a direct measurement of the degree of coupling, e.g. the amount of light power coupled to the fibre or the opto-electronic element
• CPC Class Codes: G02B 6/4226 Positioning means for moving the elements into alignment, e.g. alignment screws, deformation of the mount
• CPC Class Codes: G02B 6/4227 Active alignment methods, e.g. procedures and algorithms
• CPC Class Codes: G02B 6/4239 Adhesive bonding; Encapsulation with polymer material
• CPC Class Codes: Y10T 29/42 Piezoelectric device making
• CPC Class Codes: Y10T 29/49 Method of mechanical manufacture

Abstract

A structure for optically aligning an optical fiber to a photonic device and method of fabrication of same. The structure optically aligns an optical fiber to the photonic device using a lens between the two which is moveable by actuator heads. The lens is moveable by respective motive sources associated with the actuator heads.

Claims

1. An optical alignment structure comprising:

a lens for receiving an optical signal from a light emitting device and providing the light signal to a light receiving device, one of the light emitting device and light receiving device comprising a photonic device and the other of the light emitting and light receiving device comprising an optical fiber;

at least two lower actuator heads for causing movement of the lens, the two lower actuator heads supporting the lens from below;

an upper actuator head for causing movement of the lens, the upper actuator head contacting the lens from above; and

a motive source associated with the two lower actuator heads and the upper actuator head for causing responsive movement of the lens, wherein the lens, at least two lower actuator heads, upper actuator head, photonic device and motive source are part of an integrated photonic chip.

2. An optical alignment structure as in claim 1, wherein each of the two lower actuator head and the upper actuator head has an associated motive source for causing movement of the lens.

3. An optical alignment structure as in claim 2, wherein the integrated photonics chip further comprises respective cantilever arms associated with each of the actuator heads, the actuator heads being provided at the free ends of the respective cantilever arms.

4. An optical alignment structure as in claim 3, wherein the motive source comprises a respective piezoelectric structure associated with each cantilever arm.

5. An optical alignment structure as in claim 4, wherein each piezoelectric structure causes a bending movement of a respective cantilever arm.

6. An optical alignment structure as in claim 5, wherein the bending movements of the cantilever arms cause the actuator heads to impart movement of the lens in x, y, and z axis directions.

7. An optical alignment structure as in claim 4, wherein the cantilever arms for the two lower actuator heads are stationary and each piezoelectric structure for the two lower actuator heads is provided between a respective cantilever arm and a respective actuator head.

8. An optical alignment structure as in claim 2, wherein two of the actuator heads hold the lens from below and the motive source for the two actuator heads is a respective piezoelectric structure provided between an actuator head and a stationary support.

9. An optical alignment structure as in claim 2, wherein two of the actuator heads hold the lens from below and the motive source for the two actuator heads is a respective piezoelectric structure provided between an actuator head and the lens.

10. An optical alignment structure as in claim 9, wherein the lower actuator heads are spaced apart and positioned on opposite sides of the lens bottom such that the lens engages with the inclined areas of the actuator heads.

11. An optical alignment structure as in claim 10, wherein the respective lower actuator heads cause the lens to move in an upward direction when both lower actuator heads are moved towards one another and cause the lens to move in a downward direction when both lower actuator heads are moved away from one another.

12. An optical alignment structure as in claim 10, wherein the respective lower actuator heads cause the lens to move in a leftward direction when both heads move in leftward direction and cause the lens to move in a rightward direction when both heads move in a rightward direction.

13. An optical alignment structure as in claim 10, wherein the respective lower actuator heads cause the lens to move in an upward and leftward direction when one of the heads is stationary and the other moves in a direction towards the stationary actuator head and causes the lens to move in an upward and rightward direction when the other actuator head is stationary and the one actuator head moves in a direction towards the stationary actuator head.

14. An optical alignment structure as in claim 1, wherein the motive source comprises a respective piezoelectric structure for causing movement of a respective actuator head.

15. An optical alignment structure as in claim 14, further comprising a control system for operating the respective piezoelectric structures to cause movement of the respective actuator heads.

16. An optical alignment structure as in claim 15, wherein the control system receives a signal representing the amount of light received by the light receiving device and operates the respective piezoelectric structures to cause movement of the lens to a position which obtains optical alignment of the light emitting and light receiving devices.

17. An optical alignment structure as in claim 16, wherein the control system periodically monitors the light received by the light receiving device and, if the received light is not within a tolerance range, operates the respective piezoelectric structures to cause movement of the lens to a position which increases the amount of light received by the light receiving device.

18. An optical alignment structure as in claim 17, wherein the control system periodically monitors the light received by the light receiving device.

19. An optical alignment structure as in claim 16, wherein the light transmitting device is the optical fiber and the light receiving device is the photonic device.

20. An optical alignment structure as in claim 19, wherein the photonic device is a waveguide.

21. An optical alignment structure as in claim 16, wherein the light transmitting device is the photonic device and the light receiving device is the optical fiber.

22. An optical alignment structure as in claim 21, wherein the photonic device is a waveguide.

23. An optical alignment structure as in claim 1, wherein the actuator heads are each provided with a downwardly sloping inclined area engaging with a lower portion of the lens.

24. An optical alignment structure as in claim 23, wherein the inclined area comprises a planar area.

25. An optical alignment structure as in claim 23, wherein the inclined area comprises a curved area.

26. An optical alignment structure as in claim 23, wherein the inclined area comprises a series of steps.

27. An optical alignment structure comprising:

a lens for receiving an optical signal from a light emitting device and providing the light signal to a light receiving device, one of the light emitting device and light receiving device comprising a photonic device and the other of the light emitting and light receiving device comprising an optical fiber;

a pair of actuator heads provided at a lower surface and at opposite sides of the lens;

an actuator head provided at an upper surface of the lens;

a plurality of bendable cantilever arms for respectively supporting the actuator heads;

a plurality of piezoelectric structures respectively associated with each cantilever arm; and

a control system for controlling the piezoelectric structures to effect movement of the lens through the actuator heads.

28. An optical alignment structure as in claim 27, wherein the lens, photonic device, actuator heads, bendable cantilever arms and piezoelectric structures are fabricated on a common integrated circuit chip.

29. An optical alignment structure as in claim 28, wherein the control system is fabricated on the common integrated circuit chip.

30. An optical alignment structure as in claim 29, further comprising a signal detector for receiving a light signal from the light receiving device, the control system receiving and acting on the light signal to control the piezoelectric structures.