III-nitride light emitting device with double heterostructure light emitting region
View Patent ↗In a device, a III-nitride light emitting layer is disposed between an n-type region and a p-type region. A first spacer layer, which is disposed between the n-type region and the light emitting layer, is doped to a dopant concentration between 6×10 18 cm −3 and 5×10 19 cm −3 . A second spacer layer, which is disposed between the p-type region and the light emitting layer, is not intentionally doped or doped to a dopant concentration less than 6×10 18 cm −3 .
1. A semiconductor light emitting device comprising:
an n-type region;
a p-type region;
a III-nitride light emitting layer disposed between the n-type region and the p-type region;
a first spacer layer disposed between the n-type region and the light emitting layer, the first spacer layer being in direct contact with the light emitting layer, wherein the first spacer layer is doped to a dopant concentration between 6×10 18 cm −3 and 5×10 19 cm −3 ;
a second spacer layer disposed between the p-type region and the light emitting layer, the second spacer layer being in direct contact with the light emitting layer, wherein the second spacer layer is not intentionally doped or doped to a dopant concentration less than 6×10 18 cm −3 ; and
a blocking layer comprising aluminum, wherein the AlN composition in the blocking layer is greater than 8% and less than 30% and wherein the second spacer is disposed between the light emitting layer and the blocking layer.
2. The semiconductor light emitting device of claim 1 wherein the light emitting layer is InGaN.
3. The semiconductor light emitting device of claim 1 wherein the light emitting layer is not intentionally doped or doped to a dopant concentration less than 6×10 18 cm −3 .
4. The semiconductor light emitting device of claim 1 wherein the first spacer layer has a dopant concentration between 1×10 19 cm −3 and 5×10 19 cm −3 .
5. The semiconductor light emitting device of claim 1 wherein the light emitting layer has a thickness between 50 Å and 600 Å.
6. The semiconductor light emitting device of claim 1 wherein the first spacer layer is doped n-type with Si.
7. The semiconductor light emitting device of claim 1 wherein each of the first and second spacer layers have a thickness between 20 Å and 1000 Å.
8. The semiconductor light emitting device of claim 1 further comprising an InGaN preparation layer disposed between the n-type region and the light emitting layer.
9. The semiconductor light emitting device of claim 8 wherein the preparation layer is doped with Si to a concentration between 2×10 17 cm −3 and 2×10 19 cm −3 .
10. The semiconductor light emitting device of claim 8 wherein the preparation layer has an InN composition between 2% and 12%.
11. The semiconductor light emitting device of claim 8 wherein a top surface of the preparation layer is within 5000 Å of the light emitting layer.
12. The semiconductor light emitting device of claim 8 wherein the preparation layer has a thickness greater than 200 Å.
13. The semiconductor light emitting device of claim 1 wherein the first spacer layer is GaN.
14. The semiconductor light emitting device of claim 1 wherein the second spacer layer is GaN or AlGaN.
15. The semiconductor light emitting device of claim 1 further comprising:
contacts electrically connected to the n-type region and the p-type region.
16. The semiconductor light emitting device of claim 1 wherein the first spacer layer is more heavily doped than the second spacer layer.
17. The semiconductor light emitting device of claim 1 wherein the blocking layer is in direct contact with the second spacer layer.
18. The semiconductor light emitting device of claim 1 wherein the blocking layer is one of p-type AlGaN and p-type AlInGaN.