Long wavelength vertical cavity surface emitting lasers
View Patent ↗Long-wavelength VCSELs having top DBR mirrors with multiple levels. The individual levels of the DBR are comprised of different materials. The top DBR mirror level(s) forms a pillar structure and/or are defined by trenches. Top contacts are formed on the top DBR mirror below that mirror's top level. An aperture is formed in one of the DBR layers. An ion implanted region is formed in the top DBR and may extend into the active region and into part of a bottom DBR. The top DBRs are beneficially fabricated by etching parts of upper level(s) down to the lower level(s).
1. A Vertical Cavity Surface Emitting Laser, comprising:
a substrate having a bottom contact;
an active region over said substrate, said active region for emitting light at a predetermined wavelength in response to an applied electric current;
a bottom distributed Bragg reflector mirror disposed between said active region and said substrate, said bottom distributed Bragg reflector mirror for reflecting light emitted by said active region back toward said active region;
a top distributed Bragg reflector mirror adjacent said active region, said top distributed Bragg reflector mirror for reflecting light emitted by said active region back toward said active region; wherein said top distributed Bragg reflector mirror has a first level and a second level that partially extends over, and is adjacent to, the first level;
a top contact adjacent to said first level with no intervening layers; and
an ion implanted region in said first level.
2. A Vertical Cavity Surface Emitting Laser according to claim 1 , wherein materials comprising said first level and said second level have different etching characteristics.
3. A Vertical Cavity Surface Emitting Laser according to claim 1 , wherein said first level is comprised of a material selected from the group consisting of AlGaInAs, AlInAs, InGaAsP, and InP, and combinations thereof.
4. A Vertical Cavity Surface Emitting Laser according to claim 1 , wherein said second level is made of a material selected from the group consisting of AlGaAs, AlGaAsSb, AlGaPSb, an oxidized material, and combinations thereof.
5. A Vertical Cavity Surface Emitting Laser according to claim 1 , wherein said ion implanted region extends into said active region.
6. A Vertical Cavity Surface Emitting Laser according to claim 1 , wherein said ion implanted region extends into part of said bottom distributed Bragg reflector mirror.
7. A Vertical Cavity Surface Emitting Laser according to claim 1 , wherein said second level includes an aperture.
8. A Vertical Cavity Surface Emitting Laser according to claim 7 , wherein said second aperture is an oxidized layer.
9. A Vertical Cavity Surface Emitting Laser according to claim 7 , wherein said aperture is an air gap.
10. A Vertical Cavity Surface Emitting Laser, comprising:
a substrate having a bottom context;
an active region over said substrate, said active region for emitting light at a predetermined wavelength in response to an applied electric current;
a bottom distributed Bragg reflector mirror disposed between said active region and said substrate, said bottom distributed Bragg reflector mirror for reflecting light emitted by said active region back toward said active region;
a top distributed Bragg reflector mirror adjacent said active region, said top distributed Bragg reflector mirror for reflecting light emitted by said active region back toward said active region; wherein said top distributed Bragg reflector mirror has a first level, a second level that partially extends over the first level, a third level that extends over a part of said second level, an aperture over said first level, and top contact over said first level; and
an ion implanted region below said top contact.
11. A Vertical Cavity Surface Emitting Laser according to claim 10 , wherein said first and second levels are comprised of materials that have different etching characteristics.
12. A Vertical Cavity Surface Emitting Laser according to claim 10 , wherein said second and third levels of the top distributed Bragg reflector are comprised of materials that have different etching characteristics.
13. A Vertical Cavity Surface Emitting Laser according to claim 10 , wherein said first level is comprised of a material selected from the group consisting of lnGaAsP/InP and AlGaInAs/AlInAs, and combinations thereof.
14. A Vertical Cavity Surface Emitting Laser according to claim 10 , wherein said second level is comprised of a material selected from the group consisting of AIGaInAs/AlInAS and InGaAsP/InP, and combinations thereof.
15. A Vertical Cavity Surface Emitting Laser according to claim 10 , wherein said third level is comprised of a material selected from the group consisting of AIGaAs, AlGaAsSb, AlGaPSb, an oxidized material, and combinations thereof.
16. A Vertical Cavity Surface Emitting Laser according to claim 10 , wherein said aperture is an oxidized layer.
17. A Vertical Cavity Surface Emitting Laser according to claim 10 , wherein said aperture is an air gap.
18. A Vertical cavity Surface Emitting Laser according to claim 10 , wherein said ion implanted region extends into said first level.
19. A Vertical Cavity Surface Emitting Law according to claim 10 , wherein said ion implanted region extends into said second level.
20. A Vertical Cavity Surface Emitting Laser, comprising:
a substrate;
a bottom distributed Bragg reflector mirror over said substrate, said bottom distributed Bragg reflective mirror for reflecting light;
an active region extending over part of said bottom distributed Bragg reflector mirror, said active region for emitting light at a predetermined wavelength in response to an electric current;
a bottom contact adjacent to said bottom distributed Bragg reflector mirror with no intervening layers;
a top distributed Bragg reflector mirror adjacent said active region, said top distributed Bragg reflector mirror for reflecting light emitted by said active region back toward said active region; wherein said top distributed Bragg reflector mirror has a first level and a second level that extends over part of the first level and an aperture;
a top contact on said first level.
21. A Vertical Cavity Surface Emitting Laser according to claim 20 , wherein said first and second levels are comprised of materials that have different etching characteristics.
22. A Vertical Cavity Surface Emitting Laser according to claim 20 , wherein said first level includes a material selected from the group consisting of AlGaInAs, AlInAs, InGaAsP, and InP, and combinations thereof.
23. A Vertical Cavity Surface Emitting Laser according to claim 20 , wherein said second level is comprised of a material selected from the group consisting of AlGaAS, AlGaAsSb, AlGaPSb, an oxidized material, and combinations thereof.
24. A Vertical Cavity Surface Emitting Laser according to claim 20 , wherein said aperture is an oxidized layer.
25. A Vertical Cavity Surface Emitting Laser according to claim 20 , wherein said aperture is an air gap.
26. A Vertical Cavity Surface Emitting Laser comprising:
an active region, said active region emitting light at a predetermined wavelength in response to an applied electric current;
a bottom distributed Bragg reflector mirror adjacent to said active region, said bottom distributed Bragg reflector mirror reflecting light emitted by said active region back toward said active region;
a top distributed Bragg reflector mirror adjacent to said active region, said top distributed Bragg reflector mirror reflecting light emitted by said active region back toward said active region, wherein said top distributed Bragg reflector mirror includes a first level adjacent said active region, a second level partially extending over, and adjacent to, said first level, and an aperture over said first level;
a top contact over said first level; and
an ion implanted region below said top contact.
27. A Vertical Cavity Surface Emitting Laser according to claim 26 , wherein said top contact directly contacts said first level.
28. A Vertical Cavity Surface Emitting Laser according to claim 26 , wherein said top contact directly contacts said second level.
29. A Vertical Cavity Surfacc Emitting Laser according to claim 26 , wherein said top distributed Bragg reflector mirror further includes a third level extending over part of, and adjacent to, said second level.
30. A Vertical Cavity Surface Emitting Laser according to claim 26 , further including a bottom contact directly contacting said bottom distributed Bragg reflector mirror.
31. A Vertical Cavity Surface Emitting Laser according to claim 26 , further including a substrate adjacent said bottom distributed Bragg reflector mirror.
32. A Vertical Cavity Surface Emitting Laser according to claim 31 , further including a bottom contact separated from said bottom distributed Bragg reflector mirror by said substrate.