Solid state lighting devices without converter materials and associated methods of manufacturing

Patent metadata

Field	Value
Publication number	US-9601658-B2
Application number	US-201514810092-A
Country	US
Kind code	B2
Filing date	Jul 27, 2015
Priority date	Jul 16, 2010
Publication date	Mar 21, 2017
Grant date	Mar 21, 2017

Abstract

Solid state lighting devices that can produce white light without a phosphor are disclosed herein. In one embodiment, a solid state lighting device includes a first semiconductor material, a second semiconductor material spaced apart from the first semiconductor material, and an active region between the first and second semiconductor materials. The active region includes a first sub-region having a first center wavelength and a second sub-region having a second center wavelength different from the first center wavelength.

First claim

We claim:

1. A solid state lighting (SSL) device comprising:
a substrate material;
a first semiconductor material on the substrate material;
a second semiconductor material spaced apart from the first semiconductor material;
an active region between the first and second semiconductor materials, the active region having a first sub-region and a second sub-region proximate the first sub-region, wherein the first sub-region is configured to produce a first emission and the second sub-region is configured to produce a second emission different then the first emission, and wherein—
the first sub-region includes a first plurality of InGaN materials having a first indium concentration,
the second sub-region includes a second plurality of InGaN materials having a second indium concentration, and
at least one of the first indium concentration and the second indium concentration increases or decreases along a thickness direction of the respective sub-region,
wherein at least one of the first sub-region and the second sub-region comprises an InGaN bulk material.

2. The SSL device of claim 1 wherein the InGaN bulk material includes first areas having a generally planar surface and second areas having a plurality of pits extending into the InGaN bulk material from the generally planar surface.

3. The SSL device of claim 2 wherein:
the first areas of the InGaN bulk material include a generally planar surface and the second areas include a plurality of pits extending into the InGaN bulk material from the generally planar surface; and
the pits individually include a plurality of sidewalls extending from the generally planar surface into the InGaN bulk material.

4. The SSL device of claim 1 wherein the InGaN bulk material is configured to emit light at multiple center wavelengths.

5. The SSL device of claim 1 wherein:
the InGaN bulk material is a first InGaN bulk material having a first bulk material thickness;
the other of the first or second sub-regions comprises a second InGaN bulk material having a second bulk material thickness different from the first bulk material thickness.

6. The SSL device of claim 1 wherein the other of the first or second sub-regions comprises a multiple quantum well (MQW).

7. The SSL device of claim 1 wherein the other of the first or second sub-regions comprises a single quantum well (SQW) having an SQW active material.

8. A solid state lighting (SSL) device comprising:
a substrate material;
a first semiconductor material on the substrate material;
a second semiconductor material spaced apart from the first semiconductor material;
an active region between the first and second semiconductor materials, the active region having a first sub-region and a second sub-region proximate the first sub-region, wherein the first sub-region is configured to produce a first emission and the second sub-region is configured to produce a second emission different then the first emission, and wherein—
the first sub-region includes a first plurality of InGaN materials having a first indium concentration,
the second sub-region includes a second plurality of InGaN materials having a second indium concentration, and
at least one of the first indium concentration and the second indium concentration increases or decreases along a thickness direction of the respective sub-region,
wherein one of the first sub-region and the second sub-region comprises an MQW and the other of the first or second sub-regions comprises a single quantum well (SQW).

9. The SSL device of claim 1 wherein:
the first sub-region has a first thickness; and
the second sub-region has a second thickness different than the first thickness.

10. The SSL device of claim 1 wherein the device does not include a converter material.

11. The SSL device of claim 1 wherein the first sub-region is positioned on the second sub-region, or vice versa.

12. The SSL device of claim 8 wherein:
the first sub-region has a first thickness; and
the second sub-region has a second thickness different than the first thickness.

13. The SSL device of claim 8 wherein the device does not include a converter material.

14. The SSL device of claim 8 wherein the first and/or second sub-region includes an GaN/InGaN MQWs.

15. The SSL device of claim 8 wherein the first and second plurality of InGaN materials are separated by a plurality of passive materials.

16. The SSL device of claim 8 wherein the device is configured to emit a white light.

Assignees

• Micron Technology Inc

Inventors

• Ren Zaiyuan
• Gehrke Thomas

Classifications

• H10P14/3441

  Conductivity type · CPC title

• H10P14/3416

  Nitrides · CPC title

• H10P14/2901

  Materials · CPC title

• H10P14/24

  using chemical vapour deposition [CVD] · CPC title

• C30B25/00

  Single-crystal growth by chemical reaction of reactive gases, e.g. chemical vapour-deposition growth · CPC title