Light emitting element and manufacturing method thereof

Patent metadata

Field	Value
Publication number	US-2024282890-A1
Application number	US-202418419993-A
Country	US
Kind code	A1
Filing date	Jan 23, 2024
Priority date	Feb 16, 2023
Publication date	Aug 22, 2024
Grant date	—

Abstract

A light emitting element includes a group III nitride semiconductor with an emission wavelength of 200 nm or more and 280 nm or less, the light emitting element includes: a semiconductor layer in which an n layer, a light emitting layer, and a p layer are provided in this order; and a p-electrode provided on and in contact with the p layer, and the p-electrode includes a contact layer that is provided in contact with the p layer, has a thickness of 0.5 nm or more and 6 nm or less, and contains Ru or Ni/Au, and a reflection layer that is provided in contact with the contact layer, has a thickness of 50 nm or more, and contains Al or an alloy mainly containing Al.

First claim

What is claimed is:

1 . A light emitting element comprising a group III nitride semiconductor with an emission wavelength of 200 nm or more and 280 nm or less, the light emitting element comprising:
a semiconductor layer in which an n layer, a light emitting layer, and a p layer are provided in this order; and a p-electrode provided on and in contact with the p layer, wherein the p-electrode comprises a contact layer that is provided in contact with the p layer, has a thickness of 0.5 nm or more and 6 nm or less, and contains Ru or Ni/Au, and a reflection layer that is provided in contact with the contact layer, has a thickness of 50 nm or more, and contains Al or an alloy mainly containing Al.

2 . The light emitting element according to claim 1 , wherein the contact layer contains Ru, a contact resistivity of the p-electrode is 3×10 −3 Ω·cm 2 or less, and a reflectance at the emission wavelength is 55% or more.

3 . The light emitting element according to claim 1 , wherein the contact layer contains Ni/Au, a contact resistivity of the p-electrode is 2×10 −3 Ω·cm 2 or less, and a reflectance at the emission wavelength is 40% or more.

4 . The light emitting element according to claim 1 , wherein a region where a material for the contact layer and a material for the reflection layer are mixed is not present at an interface between the contact layer and the reflection layer.

5 . A manufacturing method of a light emitting element comprising a group III nitride semiconductor with an emission wavelength of 200 nm or more and 280 nm or less, the manufacturing method comprising:
forming a semiconductor layer by stacking an n layer, a light emitting layer, and a p layer in this order on a surface of a substrate; forming a contact layer containing Rh, Ru, or Ni/Au and having a thickness of 0.5 nm or more and 6 nm or less in contact with the p layer; performing a heat treatment to reduce a contact resistance of the contact layer to the p layer; and forming, in contact with the contact layer, a reflection layer having a thickness of 50 nm or more and containing Al or an alloy mainly containing Al to form a p-electrode in which the contact layer and the reflection layer are stacked.

6 . The manufacturing method of a light emitting element according to claim 5 , wherein the contact layer contains Rh, a contact resistivity of the p-electrode is 2×10 −2 Ω·cm 2 or less, and a reflectance at the emission wavelength is 70% or more.

7 . The manufacturing method of a light emitting element according to claim 5 , wherein the contact layer contains Ru, a contact resistivity of the p-electrode is 3×10 −3 Ω·cm 2 or less, and a reflectance at the emission wavelength is 55% or more.

8 . The manufacturing method of a light emitting element according to claim 5 , wherein the contact layer contains Ni/Au, a contact resistivity of the p-electrode is 2×10 −3 Ω·cm 2 or less, and a reflectance at the emission wavelength is 40% or more.

Assignees

• Toyoda Gosei Kk

Inventors

• Mizutani Koichi
• Omoya Hideki
• Matsui Shinichi
• Makino Hiroaki

Classifications

• H10H20/032

  of electrodes · CPC title

• H10H20/825 Primary

  containing nitrogen, e.g. GaN · CPC title

• H10H20/835 Primary

  Reflective materials · CPC title

• H10H20/832

  characterised by their material · CPC title

• H10H20/80

  Constructional details · CPC title