Partial spacers for wafer-level fabricated modules

Patent metadata

Field	Value
Publication number	US-2016247976-A1
Application number	US-201415027637-A
Country	US
Kind code	A1
Filing date	Oct 1, 2014
Priority date	Oct 8, 2013
Publication date	Aug 25, 2016
Grant date	—

Abstract

An optoelectronic module includes a cover substrate including a passive optical element, a base substrate including an optoelectronic device, and a spacer layer joining the cover substrate to the base substrate. The spacer layer includes multiple first spacer elements fixed to a surface of the cover substrate and multiple second spacer elements fixed to a surface of the base substrate, in which each first spacer element is joined to a corresponding second spacer element through an adhesive layer, and in which the cover substrate, base substrate, and spacer layer define an interior region of the module in which the optical element is aligned with the optoelectronic device.

First claim

1 . An optoelectronic module comprising:
a cover substrate comprising a passive optical element; a base substrate comprising an optoelectronic device; a spacer layer joining the cover substrate to the base substrate, wherein the spacer layer comprises a plurality of first spacer elements fixed to a surface of the cover substrate and a plurality of second spacer elements fixed to a surface of the base substrate, each first spacer element being joined to a corresponding second spacer element through an adhesive layer, and wherein the cover substrate, base substrate, and spacer layer define an interior region of the module in which the optical element is aligned with the optoelectronic device.

2 . The optoelectronic module of claim 1 , wherein the cover substrate comprises a transparent region transparent to a specified wavelength or range of wavelengths of light, and the optical element is arranged on the transparent region.

3 . The optoelectronic module of claim 1 ,
wherein the passive optical element comprises a lens, mirror or a diffuser, and wherein the optoelectronic device comprises a light emitting element that is configured to emit light having the specified wavelength or range of wavelengths or a light sensing device configured to sense light having the specified wavelength or range of wavelengths.

4 . The optoelectronic module of claim 1 ,
wherein the adhesive layer comprises an epoxy or polydimethylsiloxane (PDMS).

5 . The optoelectronic module of claim 1 , wherein a height of one or more of the first spacer elements is different from a height of one or more of the second spacer elements.

6 . The optoelectronic module of claim 1 , wherein at least (i) the first spacer elements are part of a single contiguous wafer or (ii) the second spacer elements are part of a single contiguous wafer.

7 . (canceled)

8 . The optoelectronic module of claim 1 , wherein at least (i) the first spacer elements are separate from one another or (ii) the second spacer elements are separate from one another.

9 . (canceled)

10 . The optoelectronic module of claim 1 , wherein the first spacer elements and the second spacer elements are composed of silicon.

11 . The optoelectronic module of claim 1 , wherein the first spacer elements and the second spacer elements are composed of epoxy.

12 . (canceled)

13 . (canceled)

14 . The optoelectronic module of claim 1 , further comprising a functional layer between the plurality of first spacer elements and the plurality of second spacer elements.

15 . The optoelectronic module of claim 14 , wherein the functional layer comprises a plurality of through-holes, and wherein each through-hole is aligned with an optical axis of one or more of the optical elements.

16 . (canceled)

17 . A wafer-level method of fabricating a plurality of optoelectronic device modules, the method comprising:
providing a cover substrate that includes transparent regions, the cover substrate having a respective passive optical element on each transparent region; providing a plurality of first spacer elements on a surface of the cover substrate, wherein adjacent passive optical elements are separated from one another by a respective first spacer element; providing a base substrate including a surface on which are mounted a plurality of optoelectronic devices; providing a plurality of second spacer elements on the surface of the base substrate, wherein adjacent optoelectronic devices are separated from one another by a respective second spacer element; attaching each first spacer element on the cover substrate to a corresponding second spacer element on the base substrate to form a wafer stack, such that each passive optical element is aligned with a corresponding one of the optoelectronic devices; and separating the wafer stack into a plurality of optoelectronic device modules, wherein each optoelectronic device module includes at least one of the passive optical elements and at least one of the optoelectronic devices.

18 . The wafer-level method of claim 17 , wherein each passive optical element comprises a lens, mirror or a diffuser, and wherein each optoelectronic device comprises a light emitting element or a light sensing element.

19 . The wafer-level method of claim 17 , wherein providing the plurality of first spacer elements comprises attaching a first spacer wafer to the cover substrate to provide the first spacer elements on the cover substrate; and
wherein providing the plurality of second spacer elements comprises attaching a second spacer wafer to the base substrate to provide the second spacer elements on the base substrate.

20 . (canceled)

21 . The wafer-level method of claim 17 , wherein providing the plurality of first spacer elements comprises forming the first spacer elements on the cover substrate by using a vacuum injection technique; and
wherein providing the plurality of second spacer elements comprises forming the second spacer elements on the base substrate by using a vacuum injection technique.

22 . (canceled)

23 . The wafer-level method of claim 17 , further comprising forming the passive optical elements on the transparent regions by a replication technique; and
wherein attaching the first spacer element on the cover substrate to the corresponding second spacer element on the base substrate comprises applying an adhesive to a free end of the first spacer element and/or a free end of the corresponding second spacer element.

24 . (canceled)

25 . The wafer-level method of claim 17 , wherein applying the adhesive comprises:
applying a layer of polydimethylsiloxane (PDMS) to the free end of each first spacer element and/or to the free end of each second spacer element; and curing the layer of PDMS to bond the first spacer element to the corresponding second spacer element.

26 . The wafer-level method of claim 17 , wherein applying the adhesive comprises:
applying a layer of ultraviolet (UV) curable epoxy or heat curable epoxy to the free end of each first spacer element and/or to the free end of each second spacer element; and curing the layer of UV curable epoxy or heat curable epoxy to bond the first spacer element to the corresponding second spacer element.

27 . The wafer-level method of claim 17 , wherein attaching each first spacer element on the cover substrate to a corresponding second spacer element on the base substrate to form a wafer stack further comprises:
providing a functional layer between the first spacer element and the corresponding second spacer element; and wherein the method further comprises:
bonding a first side of the functional layer to the plurality of first spacer elements; and
bonding a second opposite side of the functional layer to the plurality of second spacer elements.

28 . The wafer-level method of claim 27 , wherein the functional layer comprises a plurality of through-holes, and providing the functional layer comprises aligning each through-hole with an optical axis of a corresponding optical element, the method further comprising:
bonding a first side of the functional layer to the plurality of first spacer elements; and bonding a second opposite side of the functional layer to the plurality of second spacer elements.

29 . (canceled)

Assignees

• Heptagon Micro Optics Pte Ltd

Inventors

• Rudmann Hartmut
• Westenhöfer Susanne
• Gubser Simon

Classifications

• H01S5/183

  having only vertical cavities, e.g. vertical cavity surface-emitting lasers [VCSEL] · CPC title

• B29D11/00307

  Producing lens wafers · CPC title

• H01S5/02

  Structural details or components not essential to laser action · CPC title

• H10K59/879

  comprising refractive means, e.g. lenses · CPC title

• H10H20/8506

  Containers · CPC title