HYBRID VERTICAL CAVITY LIGHT EMITTING SOURCES

• US 20120228582A1
• Filed: 05/17/2012
• Published: 09/13/2012
• Est. Priority Date: 03/27/2009
• Status: Active Grant

• Current Assignee: Wisconsin Alumni Research Foundation (University of Wisconsin System)
• Original Assignee: Wisconsin Alumni Research Foundation (University of Wisconsin System)
• Inventors: Ma, Zhenqiang, Zhou, Weidong
• Granted Patent: US 9,941,663 B2
• Time in Patent Office: Days
• US Class Current: 257/13
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: H01S 5/11 Comprising a photonic bandgap structure
• CPC Class Codes: H01S 5/18319 comprising a periodical structure in lateral directions
• CPC Class Codes: H01S 5/18341 Intra-cavity contacts
• CPC Class Codes: H01S 5/18366 Membrane DBR, i.e. a movable DBR on top of the VCSEL
• CPC Class Codes: H01S 5/1838 Reflector bonded by wafer fusion or by an intermediate compound
• CPC Class Codes: H01S 5/34306 emitting light at a wavelength longer than 1000nm, e.g. InP based 1300 and 1500nm lasers

Abstract

Vertical cavity light emitting sources that utilize patterned membranes as reflectors are provided. The vertical cavity light emitting sources have a stacked structure that includes an active region disposed between an upper reflector and a lower reflector. The active region, upper reflector and lower reflector can be fabricated from single or multi-layered thin films of solid states materials (“membranes”) that can be separately processed and then stacked to form a vertical cavity light emitting source.

Claims

1. A vertical cavity light emitting source comprising:

(a) a lower reflector comprising a first patterned membrane comprising an array of holes;

(b) an active region disposed over the lower reflector, wherein the active region is separated from the lower reflector by at least one intra-cavity electrically conductive contact disposed between the active region and the lower reflector; and

(c) an upper reflector comprising a second patterned membrane comprising an array of holes disposed over the active region, wherein the upper reflector is separated from the active region by at least one intra-cavity electrically conductive contact disposed between the upper reflector and the active region.

2. The light emitting source of claim 1, wherein the first patterned membrane and the second patterned membrane are each patterned into a layer of solid state material having thicknesses no greater than about 0.5 μ

m.

3. The light emitting source of claim 1, wherein the holes in one or both of the first and second patterned membranes are at least partially filled with a dielectric material.

4. The light emitting source of claim 1 having a thickness of no greater than 3 μ

m, as measured from the lower surface of the first patterned membrane to the upper surface of the second patterned membrane.

5. The light emitting source of claim 1, wherein the first patterned membrane and the second patterned membrane are patterned into a layer comprising a Group IV semiconductor and the active region comprises a Group III-V semiconductor.

6. The light emitting source of claim 5, wherein the first patterned membrane and the second patterned membrane are each patterned into a layer of single crystalline silicon and the active region comprises at least one quantum well disposed between a first cladding layer and a second cladding layer.

7. The light emitting source of claim 6, wherein at least one quantum well layer comprises GaInAsP and the first and second cladding layers comprise InP.

8. The light emitting source of claim 1, wherein first patterned membrane is patterned into the silicon device layer of a silicon-on-insulator substrate.

9. The light emitting source of claim 8, wherein the buried oxide layer of the silicon-on-insulator substrate is partially etched away.

10. The light emitting source of claim 1, wherein at least one electrically conductive contact between the lower reflector and the active region and at least one electrically conductive contact between the active region and the upper reflector is mechanically flexible.

11. The light emitting source of claim 1, wherein at least one of the lower reflector and the upper reflector include a spectral trimming layer in contact with the first patterned membrane or the second patterned membrane.

12. The light emitting source of claim 1, wherein the first patterned membrane and the second patterned membrane are each patterned into a layer of single crystalline silicon and the active region comprises multiple quantum well layers of GaInAsP sandwiched between a first cladding layer of n-type InP and a second cladding layer of p-type InP.

13. The light emitting source of claim 1, wherein the second patterned membrane is selectively doped and metal contacts are formed on the upper surface of the second patterned membrane.

14. The light emitting source of claim 1, wherein the electrically conductive contacts are metal contacts.

15. The light emitting source of claim 1, wherein the reflectors do not include distributed Bragg reflectors.

16. A light emitting source array comprising a plurality of vertical cavity light emitting sources on a substrate, the vertical cavity light emitting sources comprising:

(a) a lower reflector comprising a first patterned membrane comprising an array of holes;

(b) an active region disposed over the lower reflector, wherein the active region is separated from the lower reflector by at least one intra-cavity electrically conductive contact disposed between the active region and the lower reflector; and

(c) an upper reflector comprising a second patterned membrane comprising an array of holes disposed over the active region, wherein the upper reflector is separated from the active region by at least one intra-cavity electrically conductive contact disposed between the upper reflector and the active region.

17. The light emitting source array of claim 16 comprising at least 100 vertical cavity light emitting sources.

18. The light emitting source array of claim 16, wherein different vertical cavity light emitting sources in the array are configured to emit light at different wavelengths.

19. The light emitting source array of claim 16, wherein the substrate is a silicon wafer.

20. The light emitting source of claim 16, wherein the substrate is a flexible polymeric substrate.