Substrate processing method and method of manufacturing crystalline silicon carbide (sic) substrate

A method of manufacturing a crystalline silicon carbide (SiC) substrate, the method comprising:

• a step of preparing a crystalline silicon carbide (SiC) substrate in which a predetermined impurity atom is ion-implanted;
• a step of removing an oxide film formed on the crystalline silicon carbide (SiC) substrate;
• a step of performing plasma irradiation using a gas containing at least one of an inert gas and a fluorine based gas on the crystalline silicon carbide (SiC) substrate in which the oxide film is removed;
• and
• a step of performing high temperature heating processing on the plasma-irradiated crystalline silicon carbide (SiC) substrate.

A method of manufacturing a crystalline silicon carbide (SiC) substrate, the method comprising:

• a step of preparing a crystalline silicon carbide (SiC) substrate in which a predetermined impurity atom is ion-implanted;
• a step of removing, from the crystalline silicon carbide (SiC) substrate, an oxide film formed thereon;
• a step of performing plasma irradiation on the crystalline silicon carbide (SiC) substrate so as to remove at least part of a substance, other than the crystalline silicon carbide (SiC) substrate, the substance being present on a surface of the crystalline silicon carbide (SiC) substrate in which the oxide film is removed;
• and
• a step of performing high temperature heating processing on the plasma-irradiated crystalline silicon carbide (SiC) substrate.