Optoelectronic IC module

• US 6,674,948 B2
• Filed: 08/13/2001
• Issued: 01/06/2004
• Est. Priority Date: 08/13/2001
• Status: Expired due to Fees

• Current Assignee: Kaiwood Technology Company Limited
• Original Assignee: Optics Technology, Inc.
• Inventors: Zhai, Jinhui, Yeh, Jang-Hun, Wen, Xueya
• Primary Examiner(s): Zarroli, Michael C.
• Application Number:
  US09/928,893
• Publication Number:
  US 20030031435A1
• Time in Patent Office: 876 Days
• Field of Search: 385/120, 385/89, 385/88, 438/23-25, 438/45-47, 438/22
• US Class Current: 385/120
• CPC Class Codes: G02B 6/08 with fibre bundle in form of plate
• CPC Class Codes: G02B 6/4212 the intermediate optical element being a coupling medium interposed therebetween, e.g. epoxy resin, refractive index matching material, index grease, matching liquid or gel
• 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 6/423 using guiding surfaces for the alignment
• CPC Class Codes: G02B 6/4249 comprising arrays of active devices and fibres
• CPC Class Codes: H01L 2221/68368 used in a transfer process involving at least two transfer steps, i.e. including an intermediate handle substrate
• CPC Class Codes: H01L 2224/05568 the whole external layer protruding from the surface
• CPC Class Codes: H01L 2224/05573 Single external layer
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/16 of an individual bump connector
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01025 Manganese [Mn]
• CPC Class Codes: H01L 2924/01057 Lanthanum [La]
• CPC Class Codes: H01L 2924/01079 Gold [Au]
• CPC Class Codes: H01L 2924/12041 LED

Abstract

A optoelectronic module comprises one or more VCSELs electrically connected to an IC and optically connected to a fiber optic faceplate. The fiber optic faceplate, comprising a closely packed bundle of optical fibers, permits efficient capture of light from the VCSELs. Precise alignment of the faceplate with respect to the VCSELs is not needed since light not collected by one fiber is captured by another nearby optical fiber. One method of fabricating the module comprises forming substrate layers on both sides of the VCSELs such that features can be formed on the first substrate layer while the second temporary substrate layer provides structural support. The method further comprises forming apertures on the first substrate layer by etching. An etch stop buffer layer positioned between the first substrate layer and the VCSELs protects the VCSELs from being etched in the process. The second temporary substrate layer is removed after the fiber optic faceplate is mounted on the first substrate side. An alternate method of VCSEL fabrication comprises forming an aperture by patterning a dielectric layer above an active layer within the VCSEL. The aperture in the dielectric layer can be formed with a high degree of precisely using conventional patterning techniques. The dielectric layer is part of a current confinement element that concentrates current in an active region. A top DBR can also be formed of multiple layers of dielectric.

Claims

1. An apparatus comprising:

at least one Vertical Cavity Surface Emitting Laser (VCSEL), one side of said VCSEL being mounted to a fiber optic faceplate, the other side being mounted to an IC chip wherein said VCSEL is formed on a substrate and said VCSEL emits laser light within a finite wavelength band in the optical spectrum and said substrate is substantially optically transmissive to light within said wavelength band.

2. The apparatus of claim 1, wherein said substrate layer has a thickness less than or equal to about 150 μ

m.

3. The apparatus of claim 1, further comprising an optically transmissive etch stop buffer layer interposed between said VCSEL and said substrate, wherein said etch stop buffer layer protects said VCSEL during processing.

4. The apparatus of claim 3, wherein said etch stop layer has a thickness between about 0.1 and 2 microns.

5. An apparatus comprising:

at least one Vertical Cavity Surface Emitting Laser (VCSEL), one side of said VCSEL being mounted to a fiber optic faceplate, the other side being mounted to an IC chip, wherein said VCSEL is formed on a substrate and said substrate layer has an aperture formed therein beneath said at least one VCSEL that permits passage of light from said VCSEL through said substrate.

6. The apparatus of claim 5, wherein said substrate layer has a thickness of less than or equal to about 150 μ

m.

7. The apparatus of claim 5, further comprising an optically transmissive etch stop buffer layer interposed between said VCSEL and said substrate, wherein said etch stop buffer layer substantially inhibits etching of said VCSEL during formation of said apertures in said substrate.

8. The apparatus of claim 7, wherein said etch stop layer has a thickness between about 0.1 and 2 microns.

9. An apparatus comprising:

at least one Vertical Cavity Surface Emitting Laser (VCSEL), one side of said VCSEL being mounted to a fiber optic faceplate, the other side being mounted to an IC chip, wherein said VCSEL is formed on a substrate and said fiber optic faceplate is mounted to said substrate layer with an optically transmissive adhesive.

10. The apparatus of claim 9, wherein said adhesive is a thermally curable adhesive.

11. An apparatus comprising:

at least one Vertical Cavity Surface Emitting Laser (VCSEL), one side of said VCSEL being mounted to a fiber optic faceplate, the other side being mounted to an IC chip,

wherein the IC chip has circuitry electrically connected to provide signals to said VCSEL and said VCSEL is electrically connected to said circuitry in said IC chip by conductive connections selected from the group consisting of solder bonding, thermo-compression bonding, and conductive adhesive.

12. An apparatus comprising:

at least one Vertical Cavity Surface Emitting Laser (VCSEL), one side of said VCSEL being mounted to a fiber optic faceplate, the other side being mounted to an IC chip,

wherein said VCSEL is formed over an etch stop layer that includes therein conductive vias electrically connecting said VCSEL to said IC chip.

13. An apparatus comprising:

at least one Vertical Cavity Surface Emitting Laser (VCSEL), one side of said VCSEL being mounted to a fiber optic faceplate, the other side being mounted to an IC chip, said fiber optic faceplate comprising a plurality of optical fibers arranged lengthwise parallel to provide pathways from one side of said fiber optic faceplate to another side thereof,

said fiber optic faceplate being optically coupled to a second rotated fiber optic faceplate comprising a plurality of lengthwise parallel optical fibers that provide a pathway rotated at an angle with respect to said pathways in said fiber optic faceplate optically coupled thereto, said second rotated fiber optic faceplate having a reflective surface oriented to couple light from said fiber optic faceplate mounted to said VCSEL into said second rotated fiber optic faceplate,

wherein said reflective surface is oriented at an angle between about 40°

to 50°

with respect to said plurality of lengthwise parallel optical fibers in said rotated fiber optic faceplate.

14. The apparatus of claim 13, wherein said plurality of fibers in said rotated fiber optic faceplate are cleaved at an angle between about 40°

to 50°

with respect to said plurality of lengthwise parallel optical fibers in said second rotated fiber optic faceplate.

15. The apparatus of claim 13, wherein said reflective surface is formed by polishing said plurality of fibers in said rotated fiber optic faceplate.

16. An apparatus comprising:

at least one Vertical Cavity Surface Emitting Laser (VCSEL), one side of said VCSEL being mounted to a fiber optic faceplate, the other side being mounted to an IC chip, said fiber optic faceplate comprising a plurality of optical fibers arranged lengthwise parallel to provide pathways from one side of said fiber optic faceplate to another side thereof,

said fiber optic faceplate being optically coupled to a second rotated fiber optic faceplate comprising a plurality of lengthwise parallel optical fibers that provide a pathway rotated at an angle with respect to said pathways in said fiber optic faceplate optically coupled thereto, said second rotated fiber optic faceplate having a reflective surface oriented to couple light from said fiber optic faceplate mounted to said VCSEL into said second rotated fiber optic faceplate,

wherein said reflective surface is oriented at an angle of about 45°

with respect to said plurality of lengthwise parallel optical fibers in said rotated fiber optic faceplate.

17. An apparatus comprising:

an IC chip;

at least one optoelectronic device mounted on one side to said IC chip;

a first fiber optic faceplate mounted to an opposite side of said optoelectronic device, said fiber optic faceplate comprising a plurality of optical fibers arranged lengthwise parallel to provide optical pathways between said optoelectronic device and a front face of said first fiber optic faceplate; and

a second rotated fiber optic faceplate mounted to said front face of said first fiber optic faceplate, said second rotated fiber optic faceplate comprising a plurality of lengthwise parallel optical fibers that provide a pathway rotated at an angle with respect to said lengthwise parallel optical fibers in said first fiber optic faceplate,

wherein said second rotated fiber optic faceplate has a reflective surface oriented to couple light from said first fiber optic faceplate into said second rotated fiber optic faceplate and said reflective surface is oriented at an angle between about 40°

to 50°

with respect to said plurality of lengthwise parallel optical fibers in said second rotated fiber optic faceplate.

18. The apparatus of claim 17, wherein said reflective surface is oriented at an angle of about 45°

with respect to said plurality of lengthwise parallel optical fibers in said rotated fiber optic faceplate.

19. An apparatus comprising:

an IC chip;

at least one optoelectronic device mounted on one side to said IC chip;

a first fiber optic faceplate mounted to an opposite side of said optoelectronic device, said fiber optic faceplate comprising a plurality of optical fibers arranged lengthwise parallel to provide optical pathways between said optoelectronic device and a front face of said first fiber optic faceplate; and

a second rotated fiber optic faceplate mounted to said front face of said first fiber optic faceplate, said second rotated fiber optic faceplate comprising a plurality of lengthwise parallel optical fibers that provide a pathway rotated at an angle with respect to said lengthwise a parallel optical fibers in said first fiber optic faceplate,

wherein said second rotated fiber optic faceplate comprises material selected from the group consisting essentially of plastic, glass, and Quartz, and said plurality of fibers in said second rotated fiber optic faceplate are cleaved at an angle with respect to said lengthwise parallel optical fibers in said second fiber optic faceplate.