Optical fiber assembly for connecting photonic devices to a fiber optic cable

• US 5,515,467 A
• Filed: 12/30/1994
• Issued: 05/07/1996
• Est. Priority Date: 12/30/1994
• Status: Expired due to Fees

• Current Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Webb, Brian
• Primary Examiner(s): Lee, John D.
• Assistant Examiner(s): Palmer, Phan T. H.
• Application Number:
  US08/366,934
• Time in Patent Office: 494 Days
• Field of Search: 385/88-94, 385/31, 385/14, 385/49
• US Class Current: 385/88
• CPC Class Codes: G02B 6/4292 the light guide being disconnectable from the opto-electronic element, e.g. mutually self aligning arrangements

Abstract

A connector affixed to the end of a cable of optical fibers and having alignment pins extending axially in parallel with the cable and beyond the end thereof. A substrate with alignment holes and light transmitting openings therethrough in axial alignment with the ends of the optical fibers when the alignment pins and holes are engaged. The substrate including mounting pads, electrical connection pins and electrical traces connecting the pads to the pins. A semiconductor die, with photonic devices thereon, mounted on the mounting pads of the substrate so that each photonic device is aligned with a light transmitting opening and electrically connected to the electrical connection pins. A sleeve surrounding and securing the connector to the mounting member.

Claims

1. An optical fiber assembly comprising:

an optical fiber having a connector affixed to an end of the optical fiber, the connector having alignment pins extending axially in parallel with the optical fiber and beyond the end thereof;

a mounting member having alignment holes therein positioned to receive the alignment pins and a light transmitting opening therethrough positioned to be in axial alignment with the end of the optical fiber when the alignment pins are engaged in the alignment holes, the mounting member further having mounting pads formed thereon, a plurality of electrical connection pins extending outwardly, generally parallel with the alignment holes and electrical traces connecting the mounting pads to the plurality of electrical connection pins;

a semiconductor die having a photonic device formed thereon and defining a working area and activating terminals of the photonic device, and the semiconductor die being mounted on the mounting pads of the mounting member so that the working area of the photonic device is aligned with the light transmitting opening and the activating terminals are electrically connected to the plurality of electrical connection pins; and

a sleeve surrounding the connector, the mounting member, and the electrical connection pins.

2. An optical fiber assembly as claimed in claim 1 including in addition a cured optically clear material forming an underfill between the semiconductor die and the mounting member.

3. An optical fiber assembly as claimed in claim 2 including in addition a cured potting compound positioned in the sleeve and overlying the semiconductor die and the mounting member to hold the semiconductor die and the mounting member fixedly in the sleeve.

4. An optical fiber assembly as claimed in claim 3 including in addition a stress relief member positioned in the sleeve between the sleeve and the optical fiber for relieving stress on the optical fiber.

5. An optical fiber assembly as claimed in claim 3 wherein the heat sink is affixed to a surface of the semiconductor die and to the mounting member by a thermal adhesive.

6. An optical fiber assembly as claimed in claim 1 wherein the mounting member and the semiconductor die have substantially matching temperature coefficients of expansion.

7. An optical fiber assembly as claimed in claim 6 wherein the mounting member includes ceramic.

8. An optical fiber assembly as claimed in claim 1 wherein the sleeve defines an opening for receiving therein a mating connector portion engagement with the plurality of electrical connection pins.

9. An optical fiber assembly as claimed in claim 1 including in addition a heat sink affixed to the semiconductor die.

10. An optical fiber assembly as claimed in claim 1 wherein the photonic device is one of a light emitting diode and a vertical cavity surface emitting laser.

11. An optical fiber assembly as claimed in claim 1 wherein the photonic device includes a photo diode.

12. An optical fiber assembly comprising:

a plurality of optical fibers having a connector affixed to ends of the plurality of optical fibers, the connector having alignment pins extending axially in parallel with the plurality of optical fibers and beyond the ends thereof;

a mounting member having alignment holes therein positioned to receive the alignment pins and a light transmitting opening therethrough positioned to be in axial alignment with the ends of the plurality of optical fibers when the alignment pins are engaged in the alignment holes, the mounting member further having mounting pads formed thereon, a plurality of electrical connection pins extending outwardly, generally parallel with the alignment holes and electrical traces connecting the mounting pads to the plurality of electrical connection pins;

a semiconductor die having an array of photonic devices formed thereon and defining a working area and activating terminals for each of the photonic devices, and the semiconductor die being mounted on the mounting pads of the mounting member so that the working area of the photonic device is aligned with the light transmitting opening and the activating terminals are electrically connected to the electrical connection pins;

a sleeve surrounding the connector and the mounting member; and

a potting compound disposed in the sleeve around the semiconductor die, the mounting member, and the connector.

13. An optical fiber assembly as claimed in claim 12 wherein the sleeve defines an opening for receiving therein a mating connector portion in engagement with the connector pins.

14. An optical fiber assembly as claimed in claim 12 wherein the light transmitting opening in the mounting member includes a separate hole through the mounting member in alignment with each working area of each photonic device in the array.

15. An optical fiber assembly as claimed in claim 12 including in addition a cured optically clear material forming an underfill between the semiconductor die and the mounting member.

16. An optical fiber assembly as claimed in claim 15 including in addition locks formed in the connector, wherein the potting compound is disposed in the locks to further secure the mounting member with the connector.

17. An optical fiber assembly as claimed in claim 12 including in addition a heat sink affixed to the semiconductor die.

18. An optical fiber assembly as claimed in claim 12 wherein the array of photonic devices includes one of a light emitting diode, a vertical cavity surface emitting laser or a photo diode.

19. A method of fabricating an optical fiber assembly comprising the steps of:

providing an optical fiber having a connector affixed to an end of the optical fiber, the connector having alignment pins extending axially in parallel with the optical fiber and beyond the end thereof;

forming a mounting member having alignment holes therein positioned to receive the alignment pins and a light transmitting opening therethrough positioned to be in axial alignment with the end of the optical fiber when the alignment pins are engaged in the alignment holes;

forming mounting pads on the mounting member and forming a plurality of electrical connection pins extending outwardly, generally parallel with the alignment holes and electrical traces connecting the mounting pads to the plurality of electrical connection pins;

fabricating a semiconductor die with a photonic device thereon, the photonic device defining a working area and activating terminals;

mounting the semiconductor die on the mounting pads of the mounting member so that the working area of the photonic device is aligned with the light transmitting opening and the activating terminals are electrically connected to the plurality of electrical connection pins;

inserting the alignment pins of the connector in the alignment holes of the mounting member; and

providing a sleeve and positioning the sleeve in surrounding engagement with the connector, the mounting member, and the plurality of electrical connection pins.

20. A method of fabricating an optical fiber assembly as claimed in claim 19 wherein the step of forming a mounting member includes drilling the light transmitting opening using a laser.

21. A method of fabricating an optical fiber assembly as claimed in claim 19 including, subsequent to the step of inserting the alignment pins of the connector in the alignment holes of the mounting member, a step of introducing an optically clear material forming an underfill between the semiconductor die and the mounting member and curing the optically clear material.

22. A method of fabricating an optical fiber assembly as claimed in claim 21 wherein the step of providing a sleeve and positioning the sleeve includes in addition a step of introducing a potting compound in the sleeve and overlying the semiconductor die and the mounting member and curing the potting compound to hold the semiconductor die and the mounting member fixedly in the sleeve.

23. A method of fabricating an optical fiber assembly as claimed in claim 19 including in addition a step of affixing a heat sink to the semiconductor die.

24. A method of fabricating an optical fiber assembly as claimed in claim 23 wherein the step of affixing the heat sink includes affixing the heat sink to a surface of the semiconductor die and to the mounting member by a thermal adhesive.