Enhanced room temperature mid-IR LEDs with integrated semiconductor ‘metals’

Patent metadata

Field	Value
Publication number	US-12255264-B2
Application number	US-202117358157-A
Country	US
Kind code	B2
Filing date	Jun 25, 2021
Priority date	Jun 26, 2020
Publication date	Mar 18, 2025
Grant date	Mar 18, 2025

Abstract

Mid-IR light emitting diodes (LEDs) based on type-II quantum dot (QD) active regions grown with monolithically integrated semiconductor metal layers are provided. These LEDs comprise layers of type-II semiconductor (e.g., InGaSb) quantum dots integrated into a pn junction diode (e.g., InAs) grown above a highly doped backplane, such as an n++ InAs backplane, all in the same epitaxial growth. Aspects described herein minimize non-radiate recombination times and significantly increase radiative recombination rates by controlling the emission of the emitting QDs in the near field of an optical metal.

First claim

What is claimed:

1. A semiconductor structure comprising:
a highly doped (n++) plasmonic epitaxial layer; and
a diode structure disposed above the n++ epitaxial layer,
wherein the diode structure is monolithically integrated with the highly doped (n++) plasmonic epitaxial layer in an all-epitaxial growth, and
wherein the highly doped (n++) plasmonic epitaxial layer is doped such that is optically metallic in a mid-IR range.

2. The semiconductor structure of claim 1 , wherein the diode structure comprises an n-doped InAs layer followed by a p-doped InAs layer, with an unintentionally doped layer between the n and p material forming a pn junction which contains a number quantum dot (QD) layers acting as QD emitters.

3. The semiconductor structure of claim 2 , wherein the combination of the n++ and the pn junction creates a cavity.

4. The semiconductor structure of claim 1 , wherein the highly doped (n++) epitaxial layer is in the range of about 500 nm to 1500 nm thick, and is doped to have a plasma wavelength of less than 7 μm.

5. The semiconductor structure of claim 1 , wherein the highly doped (n++) epitaxial layer has a plasma wavelength in the range of about 4 μm to 4.8 μm.

6. The semiconductor structure of claim 1 , wherein the highly doped (n++) epitaxial layer is doped at about 10 19 /cm 3 .

7. The semiconductor structure of claim 1 , wherein the doping of the highly doped (n++) epitaxial layer is high enough so that a portion of the structure behaves like an optical metal.

8. The semiconductor structure of claim 1 , wherein the structure is configured, such that when a drive current is applied to the structure, there is about no temperature degradation of emission from 77K to 300K, and outputs power greater than 1.45μ W.

9. A semiconductor structure comprising:
a plasmonic layer as a backplane; and
a mid-IR light emitting diode (LED) emitter,
wherein the mid-IR LED emitter comprises layers of type-II semiconductor quantum dots integrated into a pn junction diode grown above the backplane, all in the same epitaxial growth, and
wherein the plasmonic layer is optically metallic in the mid-IR range.

10. The semiconductor structure of claim 9 , wherein the mid-IR LED emitter is based on type-II quantum dot active regions grown with monolithically integrated semiconductor metal layers.

11. The semiconductor structure of claim 9 , wherein the plasmonic layer comprises an n++ InAs layer, wherein the type-II semiconductor is InGaSb, and the pn junction diode comprises InAs.

12. The semiconductor structure of claim 9 , wherein the backplane is a highly doped (n++) epitaxial layer in the range of about 500 nm to 1500 nm thick.

13. The semiconductor structure of claim 9 , wherein the backplane is doped at about 10 19 /cm 3 .

14. The semiconductor structure of claim 9 , where the backplane has a plasma wavelength in the range of about 4 μm to 4.8 μm.

15. The semiconductor structure of claim 9 , where the backplane is doped to have a plasma wavelength of less than 7 μm.

Assignees

• Univ Texas

Inventors

• Wasserman Daniel
• Bank Seth
• Briggs Andrew
• Nordin Leland

Classifications

• H10H20/824

  comprising only Group III-V materials, e.g. GaP · CPC title

• H10H20/811

  having quantum effect structures or superlattices, e.g. tunnel junctions · CPC title

• H10H20/812 Primary

  within the light-emitting regions, e.g. having quantum confinement structures · CPC title

• H10H20/816 Primary

  having carrier transport control structures, e.g. highly-doped semiconductor layers or current-blocking structures · CPC title

• H01L33/30

  Electricity · mapped topic