Sub pixel light emitting diodes for direct view display and methods of making the same

Patent metadata

Field	Value
Publication number	US-11069837-B2
Application number	US-201916389510-A
Country	US
Kind code	B2
Filing date	Apr 19, 2019
Priority date	Apr 20, 2018
Publication date	Jul 20, 2021
Grant date	Jul 20, 2021

Abstract

A light emitting diode (LED) includes a n-doped semiconductor material layer located over a substrate, an active region including an optically active compound semiconductor layer stack configured to emit light located over the n-doped semiconductor material layer, a p-doped semiconductor material layer located over the active region and containing a nickel doped surface region, a conductive layer contacting the nickel doped surface region of the p-doped semiconductor material, and a device-side bonding pad layer electrically connected to the conductive layer.

First claim

The invention claimed is:

1. A method of forming a light emitting diode (LED), comprising: forming a n-doped semiconductor material layer over a substrate; forming an active region including an optically active compound semiconductor layer stack configured to emit light on the n-doped semiconductor material layer; forming a p-doped semiconductor material layer on the active region; depositing a nickel layer directly on the p-doped semiconductor material layer; etching back the nickel layer to expose a nickel-doped surface region of the p-doped semiconductor layer; and forming a conductive layer on the exposed nickel-doped surface region.

2. The method of claim 1 , wherein the nickel layer is completely removed from the p-doped semiconductor material layer surface after the step of etching back the nickel layer.

3. The method of claim 1 , wherein: the conductive layer comprises a platinum layer which contacts the nickel-doped surface region of the p-doped semiconductor material layer; and the p-doped semiconductor material layer comprises p-doped gallium nitride or p-doped aluminum gallium nitride.

4. The method of claim 3 , further comprising:
forming a silver layer over the platinum layer; and
forming a device-side bonding pad layer over the silver layer.

5. The method of claim 1 , wherein: the conductive layer comprises a silver layer which contacts the nickel-doped surface region of the p-doped semiconductor material layer; and the p-doped semiconductor material layer comprises p-doped gallium nitride or p-doped aluminum gallium nitride.

6. A method of forming a light emitting diode (LED), comprising:
forming a n-doped semiconductor material layer over a substrate;
forming an active region including an optically active compound semiconductor layer stack configured to emit light on the n-doped semiconductor material layer;
forming a p-doped semiconductor material layer on the active region;
depositing a nickel layer directly on the p-doped semiconductor material layer;
etching back the nickel layer to form residual nickel layer having an effective thickness of one to three monolayers of nickel atoms, or to expose a nickel-doped surface region of the p-doped semiconductor layer; and
forming a conductive layer on the residual nickel layer or the exposed nickel-doped surface region;
wherein:
the step of etching back the nickel layer forms the residual nickel layer; and
the step of forming a conductive layer comprises depositing a transparent conductive oxide on the p-doped semiconductor layer and forming a nickel-doped conductive oxide layer between the p-doped semiconductor material layer and the conductive layer.

7. The method of claim 6 , further comprising forming a reflector on the conductive layer and forming a device-side bonding pad layer on the reflector.

Assignees

• Glo Ab

Inventors

• Danesh Fariba
• Batres Max
• Cich Michael J
• Chen Zhen

Classifications

• H10W90/00

  Package configurations · CPC title

• H10H20/0364

  of interconnections · CPC title

• H10H20/032

  of electrodes · CPC title

• H10H20/8252

  characterised by the dopants · CPC title

• H10H20/8215

  characterised by crystalline imperfections, e.g. dislocations; characterised by the distribution of dopants, e.g. delta-doping · CPC title