P-type layer for a III-nitride light emitting device
View Patent ↗A semiconductor structure includes a light emitting region, a p-type region disposed on a first side of the light emitting region, and an n-type region disposed on a second side of the light emitting region. At least 10% of a thickness of the semiconductor structure on the first side of the light emitting region comprises indium. Some examples of such a semiconductor light emitting device may be formed by growing an n-type region, growing a p-type region, and growing a light emitting layer disposed between the n-type region and the p-type region. The difference in temperature between the growth temperature of a part of the n-type region and the growth temperature of a part of the p-type region is at least 140° C.
1. A method of making a semiconductor light emitting device, the method comprising:
growing at a first temperature a portion of an n-type semiconductor region;
growing a group III-nitride light emitting layer over the n-type semiconductor region; and
growing at a second temperature a portion of a p-type semiconductor region over the light emitting layer, wherein the portion grown at the second temperature comprises indium;
wherein a difference between the first temperature and the second temperature is at least 140° C.; and
wherein at least 10% of the total thickness of all semiconductor materials grown over the light emitting layer comprises indium.
2. The method of claim 1 wherein a difference between the first temperature and the second temperature is at least 150° C.
3. The method of claim 1 wherein the first temperature is at least 1000° C.
4. The method of claim 1 wherein the second temperature is less than 900° C.
5. The method of claim 1 wherein the portion of the p-type region grown at the second temperature is AlInGaN.
6. The method of claim 1 wherein the portion of the p-type region grown at the second temperature is InGaN.
7. The method of claim 6 wherein an InN composition in the portion of the p-type region grown at the second temperature is less than 4%.
8. The method of claim 1 wherein growing a portion of a p-type region comprises growing the portion of the p-type region under an ambient comprising N 2 .
9. The method of claim 1 wherein the III-nitride light emitting layer is a first quantum well layer, the method further comprising:
growing a barrier layer overlying the first quantum well; and
growing a second quantum well overlying the barrier layer.
10. The method of claim 1 wherein the light emitting layer is configured to emit light having a peak wavelength of at least 500 nm.
11. The method of claim 1 further comprising:
forming contacts electrically connected to the n-type region and the p-type region; and
disposing a cover over the light emitting region.
12. The method of claim 1 wherein the n-type region is a single crystal region.
13. A method of making a semiconductor light emitting device, the method comprising:
growing an n-type semiconductor region, the n-type semiconductor region including at least one layer comprising indium;
growing at a first temperature a III-nitride light emitting layer over the n-type semiconductor region; and
growing at a second temperature a portion of a p-type semiconductor region over the light emitting layer, wherein the portion of the p-type semiconductor region grown at the second temperature comprises indium;
wherein a difference between the first temperature and the second temperature is no more than 150° C.; and
wherein at least 10% of the total thickness of all semiconductor materials grown over the light emitting layer comprises indium.
14. The method of claim 13 wherein the first temperature is less than 900° C.
15. The method of claim 13 wherein the second temperature is less than 900° C.