Diode having vertical structure and method of manufacturing the same
View Patent ↗A light emitting diode includes a conductive layer, an n-GaN layer on the conductive layer, an active layer on the n-GaN layer, a p-GaN layer on the active layer, and a p-electrode on the p-GaN layer. The conductive layer is an n-electrode.
1. A vertical light emitting device, comprising:
a GaN layer having multilayer structure and including an n-type layer, an active layer, and a p-type layer, the GaN layer having a first surface and a second surface;
a conductive structure on the first surface of the GaN layer, wherein the conductive structure comprises a first electrode, wherein the first electrode is in contact with the first surface of the GaN layer and a surface of the first electrode contacting the first surface of the GaN layer reflects light from the active layer back through the second surface of the GaN layer; and
a second electrode on the second surface of the GaN layer;
wherein the conductive structure is located at the bottom of the light emitting device.
2. The vertical light emitting device according to claim 1 , wherein the first electrode includes at least one material selected from a group including Al, Ti/Al, Cr/Au, and Ti/Au.
3. The vertical light emitting device according to claim 1 , further comprising a transparent contact on the GaN layer.
4. The vertical light emitting device according to claim 3 , the transparent contact is a transparent conductive oxide (TCO) layer.
5. The vertical light emitting device according to claim 3 , wherein the transparent contact includes indium-tin-oxide.
6. The vertical light emitting device according to claim 1 , wherein the second electrode includes at least one material selected from a group including Ni/Au, Pd/Au, Pd/Ni and Pt.
7. The vertical light emitting device according to claim 1 , wherein the active layer includes AlInGaN.
8. The vertical light emitting device according to claim 1 , wherein the active layer includes at least one of a quantum well layer and a double hetero structure.
9. The vertical light emitting device according to claim 8 , wherein the quantum well layer includes a multiple quantum well layer.
10. The vertical light emitting device according to claim 1 , wherein the conductive structure has substantially the same surface area as the GaN layer.
11. A vertical light emitting device, comprising:
a first GaN layer of a first conductivity;
an active layer on the first GaN layer;
a second GaN layer of a second conductivity on the active layer;
a first ohmic layer directly on the first GaN layer, wherein a surface of the first ohmic layer contacting the GaN layer reflects light from the active layer;
a second ohmic layer on a surface the second GaN layer; and
a pad over the second ohmic layer,
wherein the first ohmic layer is configured to reflect light from the active layer back through the surface of the second GaN layer.
12. The vertical light emitting device according to claim 11 , wherein the first ohmic layer includes at least one material selected from a group including Al, Ti/Al, Cr/Au, and Ti/Au.
13. The vertical light emitting device according to claim 11 , wherein the first ohmic layer includes Al having a concentration of about 99.999% or higher.
14. The vertical light emitting device according to claim 11 , wherein the first ohmic layer includes Al of about 3000 Å.
15. The vertical light emitting device according to claim 11 , further comprising a transparent contact on the second GaN layer.
16. The vertical light emitting device according to claim 15 , the transparent contact is a transparent conductive oxide (TCO) layer.
17. The vertical light emitting device according to claim 15 , wherein the transparent contact includes indium-tin-oxide.
18. The vertical light emitting device according to claim 11 , wherein the second ohmic layer includes at least one material selected from a group including Ni/Au, Pd/Au, Pd/Ni and Pt.
19. The vertical light emitting device according to claim 11 , wherein the active layer includes AlInGaN.
20. The vertical light emitting device according to claim 11 , wherein the active layer includes includes at least one of a quantum well layer and a double hetero structure.
21. The vertical light emitting device according to claim 20 , wherein the quantum well layer includes a multiple quantum well layer.
22. The vertical light emitting device according to claim 11 , further comprising a cladding layer between the first GaN layer and the active layer or between the second GaN layer and the active layer.
23. The vertical light emitting device according to claim 22 , wherein the cladding layer includes at least one material selected from a group including n-AlGaN and p-AlGaN.
24. The vertical light emitting device according to claim 11 , wherein the first ohmic layer has substantially the same surface area as the first GaN layer
25. The vertical light emitting device according to claim 11 , wherein the first conductivity is n-type and the second conductivity is p-type.
26. The vertical light emitting device according to claim 11 , wherein the first GaN layer comprises a buffer layer of the first conductivity.
27. The vertical light emitting device according to claim 11 , wherein the first conductivity is p-type and the second conductivity is n-type.
28. A diode, comprising:
a conductive structure;
an n-GaN layer on the conductive structure;
an active layer on the n-GaN layer;
a p-GaN layer on the active layer; and
a p-electrode on a surface of the p-GaN layer;
wherein the conductive structure comprises an n-electrode, wherein a surface of the n-electrode that contacts the n-GaN layer reflects lights from the active layer back through the surface of the p-GaN layer,
wherein the conductive layer is located at the bottom of the diode.