CN-115443352-B - Method for manufacturing aluminum nitride substrate, and method for forming aluminum nitride layer

Abstract

The problem to be solved by the present invention is to provide a novel technique capable of producing an AlN substrate having a large diameter. The present invention relates to a method for producing an AlN substrate, comprising a crystal growth step (S30) of forming an AlN layer (20) on a SiC base substrate (10) having a through hole (11). The present invention also relates to a method for forming an AlN layer (20), comprising a through-hole forming step (S10) of forming a through-hole (11) in a SiC base substrate (10) before forming the AlN layer (20) on the surface of the SiC base substrate (10).

Inventors

• KANEKO TADAAKI
• Tang Dao land
• Matsuhara Moeko
• NISHIO YOSHITAKA

Assignees

• 学校法人关西学院
• 东洋铝株式会社
• 丰田通商株式会社

Dates

Publication Date

20260505

Application Date

20210330

Priority Date

20200414

Claims (7)

1. 1. A method for producing an aluminum nitride substrate includes a crystal growth step of forming an aluminum nitride layer on a silicon carbide base substrate having a through-hole, Wherein the crystal growth step relatively disposes and heats the raw materials of the silicon carbide base substrate and the aluminum nitride layer to form a temperature gradient between the raw materials on a high temperature side and the silicon carbide base substrate on a low temperature side.
2. 2. The method for manufacturing an aluminum nitride substrate according to claim 1, wherein the crystal growth step is heated to form a temperature gradient in a vertical direction of the silicon carbide base substrate.
3. 3. The manufacturing method of an aluminum nitride substrate according to claim 1 or 2, wherein the crystal growth step has a lateral growth step of growing the aluminum nitride layer in a horizontal direction of the silicon carbide base substrate and a longitudinal growth step of growing the aluminum nitride layer in a vertical direction of the silicon carbide base substrate.
4. 4. The method for manufacturing an aluminum nitride substrate according to claim 1, further comprising: A through-hole forming step of forming a through-hole in the silicon carbide base substrate, and And a strained layer removal step of removing the strained layer introduced by the through-hole formation step.
5. 5. The method for manufacturing an aluminum nitride substrate according to claim 4, wherein the through-hole forming step forms a through-hole by irradiating the silicon carbide base substrate with laser light.
6. 6. The method for manufacturing an aluminum nitride substrate according to claim 4, wherein the strained layer removing step removes the strained layer of the silicon carbide base substrate by performing a heat treatment.
7. 7. The method for manufacturing an aluminum nitride substrate according to any one of claims 4 to 6, wherein the strained layer removing step etches the silicon carbide base substrate under a silicon atmosphere.

Description

Method for manufacturing aluminum nitride substrate, and method for forming aluminum nitride layer Technical Field The present invention relates to a method for manufacturing an aluminum nitride substrate, and a method for forming an aluminum nitride layer Background Generally, semiconductor substrates are manufactured by crystal growing a growth layer on a base substrate. However, there is reported a problem that it is difficult to obtain a large-caliber semiconductor substrate according to the composition of a semiconductor material for crystal growth. For example, an AlN crystal is grown by a sublimation method on a base substrate such as an aluminum nitride (AlN) substrate or a silicon carbide (SiC) substrate. In the case of crystal growth by only sublimation, there is a problem that it is difficult to obtain a semiconductor substrate having a large diameter and good crystallinity in a region where AlN crystal does not grow. In order to solve such a problem, patent document 1 describes a technique of growing an AlN crystal on a seed substrate disposed in a crystal growth chamber provided in a crystal growth container in a reaction container by a vapor phase growth method, wherein a carbon-containing gas is supplied into the crystal growth chamber during crystal growth. Prior art literature Patent literature Patent document 1 Japanese patent laid-open No. 2007-55881 Disclosure of Invention Problems to be solved by the invention The present invention provides a novel technique capable of manufacturing an AlN substrate having a large diameter. Further, the present invention has an object to provide a novel technique capable of producing an AlN substrate having a large diameter and excellent crystallinity. Means for solving the problems The present invention, which solves the above-mentioned problems, is a method for manufacturing an aluminum nitride substrate, comprising a crystal growth step of forming an aluminum nitride layer on a silicon carbide base substrate having a through hole. Thus, by forming an aluminum nitride layer on a silicon carbide base substrate having a through hole, an aluminum nitride substrate having a large diameter and excellent crystallinity can be produced. Thus, by forming an aluminum nitride layer on a silicon carbide base substrate having a through hole, an aluminum nitride substrate having a diameter equal to that of the silicon carbide base substrate can be manufactured. Therefore, by using a silicon carbide base substrate having a large diameter, a large-diameter aluminum nitride substrate can be obtained. In addition, the term "large caliber" in this specification means that an aluminum nitride layer of a large area is obtained compared with the case where an aluminum nitride layer is formed on a silicon carbide base substrate having no through-holes. In a preferred embodiment of the present invention, the crystal growth step is heated to form a temperature gradient along the vertical direction of the silicon carbide base substrate. In a preferred embodiment of the present invention, the crystal growth step causes the raw materials of the silicon carbide base substrate and the aluminum nitride layer to be disposed opposite to each other and heated to form a temperature gradient between the silicon carbide base substrate and the raw materials. In a preferred embodiment of the present invention, the crystal growth step has a lateral growth step of growing the aluminum nitride layer in a horizontal direction of the silicon carbide base substrate and a longitudinal growth step of growing the aluminum nitride layer in a vertical direction of the silicon carbide base substrate. In a preferred embodiment of the present invention, the method further comprises a through-hole forming step of forming a through-hole in the silicon carbide base substrate, and a strained layer removing step of removing the strained layer introduced by the through-hole forming step. In a preferred embodiment of the present invention, the through-hole forming step forms the through-hole by irradiating the silicon carbide base substrate with laser light. In a preferred embodiment of the present invention, the strained layer removal step removes the strained layer of the silicon carbide base substrate by performing a heat treatment. In a preferred embodiment of the present invention, the strained layer removal step etches the silicon carbide base substrate under a silicon atmosphere. The invention also relates to a method for forming the aluminum nitride layer. That is, the present invention, which solves the above-mentioned problems, is a method of forming an aluminum nitride layer, comprising a through-hole forming step of forming a through-hole in a silicon carbide base substrate before forming the aluminum nitride layer on the silicon carbide base substrate. In a preferred embodiment of the present invention, the method further comprises a strained layer removal step of removing the strained layer intro