Indium gallium nitride red light emitting diode and method of making thereof
A red-light emitting diode includes an n-doped portion, a p-doped portion, and a light emitting region located between the n-doped portion and a p-doped portion. The light emitting region includes a light-emitting indium gallium nitride layer emitting light at a peak wavelength between 600 and 750 nm under electrical bias thereacross, an aluminum gallium nitride layer located on the light-emitting indium gallium nitride layer. and a GaN barrier layer located on the aluminum gallium nitride layer.
1. A red-light emitting diode, comprising:
an n-doped portion;
a p-doped portion; and
a light emitting region located between the n-doped portion and a p-doped portion, the light emitting region comprising:
a light-emitting indium gallium nitride layer emitting light at a peak wavelength between 600 and 750 nm under electrical bias thereacross;
a III-nitride layer located directly on the light-emitting indium gallium nitride layer; and
a GaN barrier layer located directly on the III-nitride layer,
wherein the light emitting diode comprises at least one feature selected from:
(a) the light emitting diode comprises a nanowire device; or
(b) the light emitting region consists of one or two quantum wells; or
(c) the III-nitride layer comprises an aluminum gallium nitride layer which has a composition Al y Ga (1-y) N, where y is in a range from 0.3 to 1.0; or
(d) a UV emitting InGaN/GaN superlattice is located between the n-doped portion and the light emitting region.
2. The light emitting diode of claim 1 , wherein the n-doped portion comprises a single crystalline n-doped GaN portion and the p-doped portion comprises a p-doped III-nitride layer which comprises a p-doped aluminum gallium nitride layer.
3. The light emitting diode of claim 2 , further comprising at least one strain-modulating layer located between the single crystalline n-doped GaN layer and light emitting region.
4. The light emitting diode of claim 3 , wherein the at least one strain-modulating layer comprises a plurality of strain-modulating layer stacks that is located on the single crystalline n-doped GaN layer and comprises a respective intervening indium gallium nitride layer and a respective intervening GaN layer.
5. The light emitting diode of claim 4 , wherein:
the single crystalline n-doped GaN portion is a single crystalline n-doped GaN layer having a planar top surface; and
each layer within the plurality of strain-modulating layer stacks, the light-emitting indium gallium nitride layer, the III-nitride layer, and the GaN barrier layer are planar layers having a respective top surface and a respective bottom surface that are parallel to the planar top surface of the single crystalline n-doped GaN layer.
6. The light emitting diode of claim 1 , wherein:
the light-emitting indium gallium nitride layer has a composition of In x Ga (1-x) N, wherein x is in a range from 0.26 to 0.55; and
the light-emitting indium gallium nitride layer has a thickness in a range from 3 nm to 7 nm.
7. The light emitting diode of claim 6 , wherein the p-doped III-nitride layer comprises a p-doped aluminum gallium nitride layer which has a thickness in a range from 0.5 nm to 5.0 nm and the GaN barrier layer has a thickness in a range from 5 nm to 20 nm.
8. The light emitting diode of claim 7 , further comprising a p-doped GaN layer located on the p-doped aluminum gallium nitride layer.
9. The light emitting diode of claim 1 wherein the light emitting diode comprises feature (a).
10. The light emitting diode of claim 1 wherein the light emitting diode comprises feature (b).
11. The light emitting diode of claim 10 , wherein the light emitting region consists of the one quantum well which comprises:
the light-emitting indium gallium nitride layer emitting light at the peak wavelength between 600 and 750 nm under electrical bias thereacross;
the III-nitride layer located directly on the light-emitting indium gallium nitride layer; and
the GaN barrier layer located directly on the III-nitride layer.
12. The light emitting diode of claim 10 , wherein the light emitting region consists of the two quantum wells, each of which comprises:
the light-emitting indium gallium nitride layer emitting light at the peak wavelength between 600 and 750 nm under electrical bias thereacross;
the III-nitride layer located directly on the light-emitting indium gallium nitride layer; and
the GaN barrier layer located directly on the III-nitride layer.
13. The light emitting diode of claim 1 wherein the light emitting diode comprises feature (c).
14. The light emitting diode of claim 1 wherein the light emitting diode comprises feature (d).
15. The light emitting diode of claim 1 wherein the light emitting diode comprises two or more of features (a) to (d).
16. The light emitting diode of claim 1 , wherein the red-light emitting diode comprises a first light emitting diode which has a width between 1 and 100 microns located in a direct view display on a backplane, which further comprises a second green-light emitting light emitting diode a third blue-light emitting diode located on the backplane.
17. The light emitting diode of claim 1 , wherein the light-emitting indium gallium nitride layer emits light at a peak wavelength between 610 and 650 nm under electrical bias thereacross.
18. A nanowire red-light emitting diode, comprising:
an n-doped nanowire core portion;
a p-doped portion; and
a light emitting shell located on the n-doped nanowire core under the p-doped portion, the light emitting shell comprising:
a light-emitting indium gallium nitride shell emitting light at a peak wavelength between 600 and 750 nm under electrical bias thereacross;
a III-nitride shell located on the light-emitting indium gallium nitride shell; and
a GaN barrier shell located on the III-nitride shell.
19. The nanowire red-light emitting diode of claim 18 , wherein the III-nitride layer comprises a p-doped aluminum gallium nitride layer.