P-type doping layers for use with light emitting devices

• US 9,178,114 B2
• Filed: 01/17/2014
• Issued: 11/03/2015
• Est. Priority Date: 09/29/2011
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Manutius IP, Inc.
• Inventors: Ting, Steve
• Primary Examiner(s): Nguyen, Thanh T
• Application Number:
  US14/158,471
• Publication Number:
  US 20140131734A1
• Time in Patent Office: 655 Days
• Field of Search: 257/76, 257 13- 15, 257/E33.025, 257/E33.043
• US Class Current: 1/1
• CPC Class Codes: H01L 21/02458 Nitrides
• CPC Class Codes: H01L 21/02494 Structure
• CPC Class Codes: H01L 21/02505 consisting of more than two layers
• CPC Class Codes: H01L 21/0254 Nitrides
• CPC Class Codes: H01L 21/02579 P-type
• CPC Class Codes: H01L 21/02584 Delta-doping
• CPC Class Codes: H01L 21/0262 Reduction or decomposition of gaseous compounds, e.g. CVD
• CPC Class Codes: H01L 33/0075 comprising nitride compounds
• CPC Class Codes: H01L 33/025 Physical imperfections, e.g. particular concentration or distribution of impurities
• CPC Class Codes: H01L 33/24 of the light emitting region, e.g. non-planar junction
• CPC Class Codes: H01L 33/325 characterised by the doping materials

Abstract

A light emitting diode (LED) comprises an n-type Group III-V semiconductor layer, an active layer adjacent to the n-type Group III-V semiconductor layer, and a p-type Group III-V semiconductor layer adjacent to the active layer. The active layer includes one or more V-pits. A portion of the p-type Group III-V semiconductor layer is in the V-pits. A p-type dopant injection layer provided during the formation of the p-type Group III-V layer aids in providing a predetermined concentration, distribution and/or uniformity of the p-type dopant in the V-pits.

Claims

1. A light emitting device comprising:

an n-type gallium nitride layer;

an active layer adjacent to the n-type gallium nitride layer, the active layer comprising indium (In);

an electron blocking layer adjacent to the active layer; and

a p-type gallium nitride layer adjacent to the electron blocking layer,

wherein the light emitting device comprises indium (In) at an interface between the electron blocking layer and the p-type gallium nitride layer, an In intensity having a first peak in the interface and a second peak in the active layer, the first peak of the In intensity in the interface being lower than the second peak of In intensity in the active layer, and

wherein the p-type gallium nitride layer extends into one or more V-pits of the active layer.

2. The light emitting device of claim 1, wherein the active layer has a dislocation density between about 1×

10⁸ cm<sup>−

2</sup> and 5×

10⁹ cm<sup>−

2</sup>.

3. The light emitting device of claim 1, wherein the electron blocking layer comprises aluminum gallium nitride (AlGaN).

4. The light emitting device of claim 1, wherein the electron blocking layer comprises aluminum indium gallium nitride (AlInGaN).

5. The light emitting device of claim 1, wherein the first peak of the In intensity in the interface is 1/100th or lower than the second peak of the In intensity in the active layer.

6. The light emitting device of claim 1, wherein the interface is a layer comprising In and N.

7. The light emitting device of claim 1, further comprising a substrate adjacent to the n-GaN layer.

8. The light emitting device of claim 7, wherein the substrate is a silicon substrate.

9. The light emitting device of claim 1, further comprising a pit generation layer between the n-type gallium nitride layer and the active layer, the one or more V-pits generated in the pit generation layer.

10. The light emitting device of claim 1, wherein the p-type gallium nitride layer has a first portion and a second portion, the first portion disposed over the active layer, the second portion laterally bounded by the one or more V-pits.

11. The light emitting device of claim 10, wherein a concentration of a p-type dopant in the first portion is at least about 1×

10²⁰ cm<sup>−

3</sup>.

12. The light emitting device of claim 10, wherein a concentration of a p-type dopant in the second portion is at least about 1×

10²⁰ cm<sup>−

3</sup>.

13. The light emitting device of claim 10, wherein a first concentration of a p-type dopant in the first portion and a second concentration of a p-type dopant in the second portion are at least about 1×

10^°

cm<sup>−

3</sup>.