III-nitride semiconductor light emitting device
View Patent ↗The present invention relates to an III-nitride semiconductor light emitting device in which a single layer or plural layers made of Si x C y N z (x≧0, y≧0, x+y>0, z>0) are inserted into or under an active layer and it is directed to a technology in which Al(x)Ga(y)In(1−x−y)N(0≦x≦1, 0≦y≦1, 0≦x+y≦1) of the hexagonal structure and Si x C y N z (x≧0, y≧0, x+y>0, z>0) of the hexagonal structure are combined together in view of the properties of the Si x C y N z (x≧0, y≧0, x+y>0, z>0) material.
1. A III-nitride semiconductor light emitting device comprising:
a substrate; and,
a plurality of nitride semiconductor layers being grown on the substrate and having an active layer for generating photons through recombination of electrons and holes,
wherein the active layer includes a light emitting layer that generates photons through recombination of electrons and holes, and a barrier layer which is grown on the light emitting layer and confines the electrons and holes to the light emitting layer, and
wherein the light emitting layer includes a Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer, and a nitride semiconductor layer which is grown on the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer and includes Ga and N.
2. The III-nitride semiconductor light emitting device of claim 1 , wherein the nitride semiconductor layer including Ga and N is formed as a plurality of three-dimensional islands due to the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer.
3. The III-nitride semiconductor light emitting device of claim 1 , wherein the nitride semiconductor layer including Ga and N is made of In(x)Ga(1−x)N(0<x≦1).
4. The III-nitride semiconductor light emitting device of claim 1 , wherein the barrier layer has a band gap energy larger than that of the nitride semiconductor layer including Ga and N.
5. The III-nitride semiconductor light emitting device of claim 1 , wherein the growth temperature of the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer ranges from 400° C. to 1100° C.
6. The III-nitride semiconductor light emitting device of claim 1 , wherein the thickness of the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer ranges from 2.5 Å to 10 Å.
7. The III-nitride semiconductor light emitting device of claim 1 , wherein the active layer includes a plurality of stacked structures and each of stacked structures is composed of the light emitting layer and the barrier.
8. The III-nitride semiconductor light emitting device of claim 7 , wherein the uppermost light emitting layer of the plurality of stacked structures is composed of a nitride semiconductor layer including GaN and N without the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer.
9. The III-nitride semiconductor light emitting device of claim 8 , wherein the nitride semiconductor layer including Ga and N is made of In(x)Ga(1−x)N(0<x≦1).
10. The III-nitride semiconductor light emitting device of claim 1 , wherein the silicon source of the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer is at least one selected from the group consisting of DTBSi, SiH 4 and Si 2 H 6 , the carbon source of the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer is at least one selected from the group consisting of CBr 4 , CCl 4 , and CH 4 , and the nitrogen source of the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer is at least one selected from the group consisting of NH 3 and a hydrazine-based source material.
11. a III-nitride semiconductor light emitting device comprising:
a substrate;
a plurality of nitride semiconductor layers being grown on the substrate and having an active layer with one or more light emitting layers emitting light through recombination of electrons and holes; and,
a Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer which is located under a light emitting layer located at the farthest from the substrate among the one or more light emitting layers and is not brought into contact with the substrate.
12. The III-nitride semiconductor light emitting device of claim 11 , wherein the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer is located within a range of 0.5 μm from the active layer.
13. The III-nitride semiconductor light emitting device of claim 11 , wherein the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer is located under the active layer.
14. The III-nitride semiconductor light emitting device of claim 13 , wherein the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer is located within a range of 0.5 μm from the active layer.
15. The III-nitride semiconductor light emitting device of claim 11 , wherein the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer is located within the active layer.
16. The III-nitride semiconductor light emitting device of claim 15 , wherein the active layer comprises a barrier layer, the barrier layer being located under a light emitting layer located at the farthest from the substrate among the one or more light emitting layers, having a band gap energy larger than that of the light emitting with which the barrier layer is brought into contact, and including the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer.
17. The III-nitride semiconductor light emitting device of claim 11 , wherein a light emitting layer that is located over the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer and is located at the nearest from the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer among the one or more light emitting layers, is composed of a plurality of islands.
18. The III-nitride semiconductor light emitting device of claim 11 , wherein the growth temperature of the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer ranges from 400° C. to 1100° C.
19. The III-nitride semiconductor light emitting device of claim 13 , wherein the thickness of the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer ranges from 2.5 Å to 500 Å.
20. The III-nitride semiconductor light emitting device of claim 15 , wherein the thickness of the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer ranges from 2.5 Å to 500 Å.
21. The III-nitride semiconductor light emitting device of claim 16 , wherein the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer is located at the uppermost portion of the light emitting layer.
22. The III-nitride semiconductor light emitting device of claim 21 , wherein the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer is associated with the light emitting layer with which the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer is directly contacted, and the associated light emitting layer and Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer form a light emitting layer.
23. The III-nitride semiconductor light emitting device of claim 21 , wherein the thickness of the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer ranges from 2.5 Å to 10 Å.
24. The III-nitride semiconductor light emitting device of claim 11 , wherein the silicon source of the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer is at least one selected from the group consisting of DTBSi, Si 2 H 4 and SiH 6 , the carbon source of the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer is at least one selected from the group consisting of CBr 4 , CCl 4 , and CH 4 , and the nitrogen source of the Si x C y N z (x≧0, y≧0, x+y>0, z>0) layer is at least one selected from the group consisting of NH 3 and a hydrazine-based source material.
25. The III-nitride semiconductor light emitting device of claim 11 , at least one of the one or more light emitting layers is made of In(x)Ga(1−x)N(0<x≦1).