Photonic Chip/Optical Device for Aligning and Connecting an Optical Fiber and a Photonic Integrated Waveguide and Method of its Production

Patent metadata

Field	Value
Publication number	US-2018372960-A1
Application number	US-201815988379-A
Country	US
Kind code	A1
Filing date	May 24, 2018
Priority date	Jun 21, 2017
Publication date	Dec 27, 2018
Grant date	—

Abstract

A photonic chip includes a connecting means, a substrate, and a waveguide layer. The photonic integrated waveguide and the optical fiber each have a front end portion. The connecting means includes a groove configured to receive the front end portion of the optical fiber. The groove is essentially U-shaped in its cross section, and the groove has a bottom surface and two inner side surfaces. A least one of both inner side surfaces of the U-shaped groove has a coating of an elastic material configured to hold in place the optical fiber after it is inserted into the groove. The invention further relates to an optical device which includes a photonic chip and an optical fiber, as well as a method or production of such a photonic chip.

First claim

1 . A photonic chip comprising a connecting means for aligning and connecting an optical fiber to a photonic integrated waveguide provided on the photonic chip,
(a) wherein the photonic chip at least comprises a substrate and a waveguide layer, which is provided on or within an upper portion of the substrate and which defines the photonic integrated waveguide, (b) wherein the photonic integrated waveguide and the optical fiber each have a front end portion, each front end portion having an optical axis and a front surface, (c) wherein the connecting means comprises a groove configured to receive the front end portion of the optical fiber, in such a way that front surfaces of the photonic integrated waveguide and the optical fiber are positioned opposite each other and that the optical axes of the photonic integrated waveguide and the optical fiber are essentially aligned with each other, and (d) wherein the groove is essentially U-shaped in its cross section, the groove has a bottom surface and two inner side surfaces, and at least one of the both inner side surfaces of the U-shaped groove has a coating of an elastic material configured to hold in place the optical fiber after it is inserted into the groove.

2 . The photonic chip of claim 1 , wherein both inner side surfaces of the U-shaped groove have a coating of an elastic material configured to hold in place the optical fiber after it is inserted into the groove.

3 . The photonic chip of claim 1 , wherein the groove is provided on a waveguide layer side of the chip, and the bottom surface of the groove is parallel to the optical axis of the end portion of the photonic integrated waveguide.

4 . The photonic chip of claim 1 , wherein the groove extends from a lateral end of the photonic chip to the front surface of the front end portion of the photonic integrated waveguide.

5 . The photonic chip of claim 1 , wherein the inner side surfaces of the U-shaped groove have an essentially constant distance which is greater than the diameter of the end portion of the optical fiber and wherein the coating(s) of the inner side surface(s) has/have essentially constant thickness(es) chosen in such a way that the distance of the inner side surfaces after coating is smaller than the diameter of the front end portion of the optical fiber.

6 . The photonic chip of claim 1 , wherein the distance between the bottom surface of the groove and the optical axis of the front end portion of the photonic integrated waveguide is essentially equal to the radius of the optical fiber.

7 . The photonic chip of claim 1 , wherein the coating(s) of the inner side surface(s) of the U-shaped groove is/are configured such that the optical fiber is clamped between the coated inner side surfaces of the U-shaped groove.

8 . The photonic chip of claim 2 , wherein the coatings of both sides of the inner side surfaces of the U-shaped groove have essentially the same thickness.

9 . The photonic chip of claim 1 , wherein the front end portion of the photonic integrated waveguide has the form of a taper.

10 . An optical device comprising a photonic chip and an optical fiber connected to a photonic integrated waveguide provided on the photonic chip by connecting means,
(a) wherein the photonic chip comprises a substrate and a waveguide layer which is provided on or within an upper portion of the substrate and which defines the photonic integrated waveguide, (b) wherein the photonic integrated waveguide and the optical fiber each have a front end portion, each front end portion having an optical axis and a front surface, (c) wherein the connecting means comprise a groove configured to receive the front end portion of the optical fiber, in such a way that front surfaces of the photonic integrated waveguide and the optical fiber are positioned opposite each other and that the optical axes of the photonic integrated waveguide and the optical fiber are essentially aligned with each other, and (d) wherein the groove is essentially U-shaped in its cross section, the groove has a bottom surface and two inner side surfaces, and at least one of both inner side surfaces of the U-shaped groove has a coating of an elastic material configured to hold in place the optical fiber after it is inserted into the groove.

11 . The optical device of claim 10 , wherein both inner side surfaces of the U-shaped groove have a coating of an elastic material configured to hold in place the optical fiber after it is inserted into the groove.

12 . The optical device of claim 10 , wherein the front end portion of the optical fiber has a tapered front end portion and/or a lensed tip of the front end portion.

13 . The optical device of claim 10 , wherein the front end portion of the optical fiber is additionally mechanically fixated to the chip.

14 . A method of producing the photonic chip according to claim 1 , comprising:
(a) providing a photonic chip comprising a substrate and a waveguide layer which is provided on or within an upper portion of the substrate and which defines a photonic integrated waveguide, wherein the photonic integrated waveguide has a front end portion, which has a front surface and an optical axis; (b) etching a U-shaped groove having a bottom surface and two inner side surfaces into the photonic chip, the groove essentially extending from the front surface of the front end portion of the photonic integrated waveguide in the direction of the optical axis of the front end portion of the photonic integrated waveguide; and (c) applying a coating of an elastic material on at least one of the inner side surfaces of the U-shaped groove, (d) wherein the groove and the coating(s) of the inner side surfaces are configured to receive and hold in place a front end portion of an optical fiber.

15 . The method according to claim 14 , wherein the applying the coating of the elastic material on at least one of the inner side surfaces of the U-shaped groove is carried out by filling the groove with the elastic material and subsequently removing a central portion of the elastic material by etching in such a way that the coating remains on at least one of the inner side surfaces.

16 . The method according to claim 14 , wherein the etching of the elastic material is carried out by using an etching process which does not attack the material of the photonic chip.

17 . The optical device according to claim 13 , wherein the optical fiber is mechanically fixated to the chip by gluing.

18 . The photonic chip of claim 2 , wherein the groove is provided on a waveguide layer side of the chip, and the bottom surface of the groove is parallel to the optical axis of the end portion of the photonic integrated waveguide.

19 . The method according to claim 16 , wherein the etching process uses an etching material.

20 . The method according to claim 16 , wherein the etching process does not attack the material of the substrate.

Assignees

• Adva Optical Networking Se

Inventors

• Wohlfeil Benjamin

Classifications

• G02B6/3652 Primary

  the additional structures being prepositioning mounting areas, allowing only movement in one dimension, e.g. grooves, trenches or vias in the microbench surface, i.e. self aligning supporting carriers · CPC title

• G02B6/3684

  characterised by the manufacturing process of surface profiling of the supporting carrier (manufacturing microsystems per se B81C1/00015) · CPC title

• G02B6/4233

  Active alignment along the optical axis and passive alignment perpendicular to the optical axis · CPC title

• G02B6/30 Primary

  for use between fibre and thin-film device · CPC title