Method for manufacturing aluminum nitride substrate, aluminum nitride substrate, and method for forming aluminum nitride layer

Patent metadata

Field	Value
Publication number	US-12509795-B2
Application number	US-202117996189-A
Country	US
Kind code	B2
Filing date	Mar 30, 2021
Priority date	Apr 14, 2020
Publication date	Dec 30, 2025
Grant date	Dec 30, 2025

Abstract

An object of the present invention is to provide a novel technique capable of manufacturing a large-diameter AlN substrate.
The present invention is a method for manufacturing an AlN substrate, including a crystal growth step S 30 of forming an AlN layer 20 on a SiC underlying substrate 10 having through holes 11 . In addition, the present invention is a method for forming an AlN layer including the through hole formation step S 20 of forming the through holes 11 in the SiC underlying substrate 10 before forming the AlN layer 20 on the SiC underlying substrate 10.

First claim

The invention claimed is:

1 . A method for manufacturing an aluminum nitride substrate, the method comprising a crystal growth step of forming an aluminum nitride layer on a silicon carbide underlying substrate having through holes, wherein the crystal growth step comprises disposing the silicon carbide underlying substrate and a source of the aluminum nitride layer to face each other and heating the silicon carbide underlying substrate and the source in such a way to form a temperature gradient between the silicon carbide underlying substrate and the source.

2 . The method for manufacturing an aluminum nitride substrate according to claim 1 , wherein the crystal growth step is a step of heating such that a temperature gradient is formed along a vertical direction of the silicon carbide underlying substrate.

3 . The method for manufacturing an aluminum nitride substrate according to claim 1 , wherein the crystal growth step includes a lateral growth step of growing the aluminum nitride layer in a horizontal direction of the silicon carbide underlying substrate, and a longitudinal growth step of growing the aluminum nitride layer in a vertical direction of the silicon carbide underlying substrate.

4 . The method for manufacturing an aluminum nitride substrate according to claim 1 , the method further comprising:
a through hole formation step of forming through holes in the silicon carbide underlying substrate; and a strained layer removal step of removing a strained layer introduced in the through hole formation step.

5 . The method for manufacturing an aluminum nitride substrate according to claim 4 , wherein the through hole formation step is a step of forming the through holes by irradiating the silicon carbide underlying substrate with a laser.

6 . The method for manufacturing an aluminum nitride substrate according to claim 4 , wherein the strained layer removal step is a step of removing a strained layer of the silicon carbide underlying substrate by heat treatment.

7 . The method for manufacturing an aluminum nitride substrate according to claim 4 , wherein the strained layer removal step is a step of etching the silicon carbide underlying substrate under a silicon atmosphere.

8 . A method of forming an aluminum nitride layer, the method comprising:
a through hole formation step of forming through holes in a silicon carbide underlying substrate before forming an aluminum nitride layer on a surface of the silicon carbide underlying substrate, and a crystal growth step of forming the aluminum nitride layer on the silicon carbide underlying substrate having through holes, wherein the crystal growth step comprises disposing the silicon carbide underlying substrate and a source of the aluminum nitride layer to face each other and heating the silicon carbide underlying substrate and the source in such a way to form a temperature gradient between the silicon carbide underlying substrate and the source.

9 . The method according to claim 8 , comprising a strained layer removal step of removing a strained layer introduced in the through hole formation step.

10 . The method according to claim 9 , wherein the strained layer removal step is a step of etching the silicon carbide underlying substrate by heat treatment.

11 . The method for manufacturing an aluminum nitride substrate according to claim 2 , wherein the crystal growth step is a step of disposing the silicon carbide underlying substrate and a source of the aluminum nitride layer to face each other and heating the silicon carbide underlying substrate and the source in such a way to form the temperature gradient between the silicon carbide underlying substrate and the source.

12 . The method for manufacturing an aluminum nitride substrate according to claim 2 , wherein the crystal growth step includes a lateral growth step of growing the aluminum nitride layer in a horizontal direction of the silicon carbide underlying substrate, and a longitudinal growth step of growing the aluminum nitride layer in a vertical direction of the silicon carbide underlying substrate.

13 . The method for manufacturing an aluminum nitride substrate according to claim 11 , wherein the crystal growth step includes a lateral growth step of growing the aluminum nitride layer in a horizontal direction of the silicon carbide underlying substrate, and a longitudinal growth step of growing the aluminum nitride layer in a vertical direction of the silicon carbide underlying substrate.

14 . The method for manufacturing an aluminum nitride substrate according to claim 13 , the method further comprising:
a through hole formation step of forming through holes in the silicon carbide underlying substrate; and a strained layer removal step of removing a strained layer introduced in the through hole formation step.

15 . The method for manufacturing an aluminum nitride substrate according to claim 14 , wherein the through hole formation step is a step of forming the through holes by irradiating the silicon carbide underlying substrate with a laser.

16 . The method for manufacturing an aluminum nitride substrate according to claim 15 , wherein the strained layer removal step is a step of removing a strained layer of the silicon carbide underlying substrate by heat treatment.

17 . The method for manufacturing an aluminum nitride substrate according to claim 16 , wherein the strained layer removal step is a step of etching the silicon carbide underlying substrate under a silicon atmosphere.

18 . A method of forming an aluminum nitride layer, the method comprising:
a crystal growth step of forming the aluminum nitride layer on a silicon carbide underlying substrate having through holes, wherein the crystal growth step comprises disposing the silicon carbide underlying substrate and a source of the aluminum nitride layer to face each other and heating the silicon carbide underlying substrate and the source in such a way to form a temperature gradient between the silicon carbide underlying substrate and the source.

Assignees

• Kwansei Gakuin Educational Found
• Toyo Aluminium Kk
• Toyota Tsusho Corp

Inventors

• Kaneko Tadaaki
• Dojima Daichi
• Matsubara Moeko
• Nishio Yoshitaka

Classifications

• H10P14/3416

  Nitrides · CPC title

• H10P14/2925

  Surface structures · CPC title

• H10P14/2904

  Silicon carbide · CPC title

• C30B29/403

  AIII-nitrides · CPC title

• C30B23/063

  Heating of the substrate · CPC title