LED structures for reduced non-radiative sidewall recombination

Patent metadata

Field	Value
Publication number	US-9601659-B2
Application number	US-201615199803-A
Country	US
Kind code	B2
Filing date	Jun 30, 2016
Priority date	Jan 6, 2015
Publication date	Mar 21, 2017
Grant date	Mar 21, 2017

Abstract

LED structures are disclosed to reduce non-radiative sidewall recombination along sidewalls of vertical LEDs including p-n diode sidewalls that span a top current spreading layer, bottom current spreading layer, and active layer between the top current spreading layer and bottom current spreading layer.

First claim

What is claimed is:

1. A light emitting diode (LED) comprising:
a p-n diode layer including:
a top doped layer doped with a first dopant type;
a bottom doped layer doped with a second dopant type opposite the first dopant type;
an active layer between the top doped layer and the bottom doped layer; and
p-n diode layer sidewalls spanning the top doped layer, the active layer, and the bottom doped layer;
wherein lateral edges of the active layer are internally confined inside the p-n diode layer sidewalls.

2. The LED of claim 1 , further comprising an intermixed region surrounding the active layer and within the p-n diode layer sidewalls.

3. The LED of claim 2 , wherein the active layer includes a plurality of quantum well layers and a plurality of quantum barrier layers.

4. The LED of claim 3 , wherein the intermixed region comprises a higher bandgap than each of the plurality of quantum well layers.

5. The LED of claim 4 , wherein the intermixed region comprises a higher concentration of Al than each of the plurality of quantum well layers.

6. The LED of claim 4 , wherein the intermixed region comprises a lower concentration of In than each of the plurality of quantum well layers.

7. The LED of claim 4 , wherein the intermixed region comprises:
a higher concentration of Al than each of the plurality of quantum well layers; and
a lower concentration of In than each of the plurality of quantum well layers.

8. The LED of claim 4 , wherein the bottom doped layer is in-situ doped with a dopant of the second dopant type.

9. The LED of claim 8 , further comprising a profile of a second dopant of the second dopant type spanning the p-n diode layer sidewalls along the top doped layer, the active layer, and the bottom doped layer.

10. The LED of claim 9 , wherein the dopant of the second dopant type is Mg, and the second dopant of the second dopant type is Zn.

11. The LED of claim 9 , wherein the dopant of the second dopant type is Mg, and the second dopant of the second dopant type is Mg.

12. The LED of claim 4 , wherein each of the plurality of quantum well layers is thinner than each of the plurality of quantum barrier layers.

13. The LED of claim 12 , wherein each of the plurality of quantum well layers is 2-5 nm thick.

14. The LED of claim 4 , wherein each of the quantum barrier layers and each of the active layers comprises (Al x Ga (1−x)y In 1−y P, wherein Δx between the quantum barrier layers and the active layers is greater than 0.6, and the quantum barrier layers have a higher Al concentration than the active layers.

15. The LED of claim 4 , wherein each of the quantum barrier layers and each of the active layers comprises (Al x Ga (1−x)y In 1−y P, wherein Δx between the quantum barrier layers and the active layers is greater than 0.8, and the quantum barrier layers have a higher Al concentration than the active layers.

16. The LED of claim 15 , wherein x=1 for each of the quantum barrier layers.

17. The LED of claim 4 , wherein each of the quantum well layers is under compression.

18. The LED of claim 17 , wherein the intermixed region comprises a lower concentration of In than each of the plurality of quantum well layers.

19. The LED of claim 17 , wherein each of the quantum barrier layers is under tension.

Assignees

• Apple Inc

Inventors

• Bour David P
• Mcgroddy Kelly
• Haeger Daniel Arthur
• Perkins James Michael
• Chakraborty Arpan
• Drolet Jean-Jacques P
• Sizov Dmitry S

Classifications

• H01L33/0025

  Electricity · mapped topic

• H01L33/06 Primary

  Electricity · mapped topic

• H01L33/24

  Electricity · mapped topic

• H01L33/30

  Electricity · mapped topic

• H01L33/20

  Electricity · mapped topic