Long wavelength vertical cavity surface emitting laser

• US 20010050934A1
• Filed: 05/31/2001
• Published: 12/13/2001
• Est. Priority Date: 05/31/2000
• Status: Active Grant

• Current Assignee: National Technology & Engineering Solutions Of Sandia LLC (Honeywell International Inc.)
• Original Assignee: Sandia Corporation (Martin Marietta Corporation)
• Inventors: Choquette, Kent D., Klem, John F.
• Granted Patent: US 6,931,042 B2
• Time in Patent Office: Days
• US Class Current: 372/50.11
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: H01S 5/18311 using selective oxidation
• CPC Class Codes: H01S 5/1833 with more than one structure
• CPC Class Codes: H01S 5/3054 p-doping
• CPC Class Codes: H01S 5/3095 Tunnel junction
• CPC Class Codes: H01S 5/34306 emitting light at a wavelength longer than 1000nm, e.g. InP based 1300 and 1500nm lasers

Abstract

Selectively oxidized vertical cavity lasers emitting near 1300 nm using InGaAsN quantum wells are reported for the first time which operate continuous wave below, at and above room temperature. The lasers employ two n-type Al_0.94Ga_0.06As/GaAs distributed Bragg reflectors each with a selectively oxidized current aperture adjacent to the active region, and the top output mirror contains a tunnel junction to inject holes into the active region. Continuous wave single mode lasing is observed up to 55° C.

Claims

1. A vertical cavity surface emitting laser comprising:

a substrate;

a first mirror adjacent the substrate;

an active region including one or more quantum wells, the quantum wells being formed of InGaAsN;

a second mirror adjacent the active region, the second mirror including a tunnel junction for injecting holes into the active region,

wherein the laser emits light at a nominal wavelength of 1300 nm.

2. The vertical cavity surface emitting laser of

claim 1

, wherein the substrate includes GaAs.

3. The vertical cavity surface emitting laser of

claim 1

, wherein the tunnel junction includes a n-type layer and a p-type layer.

4. The vertical cavity surface emitting laser of

claim 3

, wherein the p-type layer of the tunnel junction is positioned at or near a standing wave null in optical field.

5. The vertical cavity surface emitting layer of

claim 2

, further comprising one or more oxide apertures, proximate to the active region, wherein the oxide aperture includes an oxidized portion therein.

6. The vertical cavity surface emitting layer of

claim 5

wherein the oxidized portion of the oxide aperture comprises an aluminum oxide.

7. The vertical cavity surface emitting layer of

claim 5

wherein the oxide aperture comprises a carbon doped spike positioned at or near a standing wave null in optical field.

8. The vertical cavity surface emitting layer of

claim 5

, further comprising a mesa extending downward at least to the oxide aperture.

9. The vertical cavity surface emitting layer of

claim 1

wherein the first and second mirrors comprise unipolar distributed Bragg reflector mirrors.

10. The vertical cavity surface emitting layer of

claim 9

wherein the first and second mirrors are n-type mirrors.

11. The vertical cavity surface emitting layer of

claim 1

further comprising an upper electrode above the second mirror stack and a lower electrode below the active region.

12. The vertical cavity surface emitting layer of

claim 11

wherein the lower electrode includes an annular aperture therein to monitor transmitted output power of the VCSEL from light emitted through the annular aperture in the lower electrode.

13. A method of manufacturing a surface emitting laser that emits light at a nominal wavelength of 1300 nm., comprising:

forming a first mirror on a substrate;

forming an active region having one or more InGaAsN quantum wells on the substrate;

forming a current constriction proximate the active region;

forming a second mirror above the active region; and

forming a tunnel junction in the second mirror, wherein the tunnel junction comprises an n-type region and a p-type region and the p-type region is positioned at or near a standing wave null in optical field.

14. The method of

claim 13

wherein the step of forming a current constriction comprises forming oxide aperture layers proximate to said active region.

15. The method of

claim 14

wherein the step of forming oxide aperture layers proximate to said active region comprises forming at least one aluminum alloy layer proximate to said active region.

16. The method of

claim 15

further comprising forming a mesa downward from upper most surface of the surface emitting laser to the oxide aperture layers and oxidizing an annular portion of said oxide aperture layers.

17. The method of

claim 15

wherein the step of forming oxide aperture layers further comprises doping each aluminum alloy layer with an n-type or p-type dopant.

18. The method of

claim 17

wherein the step of doping the aluminum alloy layer with the p-type dopant further comprises forming a carbon doped spike in said aluminum alloy layer, wherein said carbon doped spike is positioned at or near a standing wave null in optical field.

19. The method of

claim 13

further comprising doping the first and second mirrors with an n-type dopant.

20. The method of

claim 13

wherein the step of forming said second mirror comprises forming one or more pairs of semiconductor mirror layers, wherein one layer in each pair has an index of refraction that is different from the index of refraction of the other layer in each pair.

21. The method of

claim 20

wherein the step of forming said semiconductor mirror layers comprises forming one quarter wavelength thick alternating layers of AlGaAs and GaAs, wherein said tunnel junction is formed into the GaAs layer nearest said active region.

22. The method of

claim 13

further comprising forming an upper electrode above the second mirror and forming a lower electrode below the active region.

23. The method of

claim 22

wherein the steps of forming the upper and lower electrodes comprises forming at least one of the upper and lower electrodes having an annular aperture therein.