Method of manufacturing silicon carbide semiconductor device

A method of manufacturing a silicon carbide semiconductor device, the method comprising:

• forming a first silicon carbide layer of a first conductivity type on a front surface of a silicon carbide semiconductor substrate;
• forming a thermal oxidation film on a surface of a base body including the first silicon carbide layer;
• removing the thermal oxidation film by a solution containing hydrofluoric acid;
• washing the base body with a mixture of ammonia water and a hydrogen peroxide solution, a mixture of hydrochloric acid and a hydrogen peroxide solution, and a dilute hydrofluoric acid;
• holding the base body at a temperature of 700 degrees C. to 1000 degrees C. in a hydrogen atmosphere;
• and
• depositing an insulating film on the base body.

A method of manufacturing a silicon carbide semiconductor device, the method comprising:

• forming a first silicon carbide layer of a first conductivity type on a front surface of a silicon carbide semiconductor substrate;
• forming a thermal oxidation film on a surface of a base body including the first silicon carbide layer;
• removing the thermal oxidation film by a solution containing hydrofluoric acid;
• washing the base body with a mixture of ammonia water and a hydrogen peroxide solution, a mixture of hydrochloric acid and a hydrogen peroxide solution, and a dilute hydrofluoric acid;
• holding the base body at temperature of 700 degrees C. to 1700 degrees C. in a mixed gas atmosphere containing hydrogen and silane;
• and
• depositing an insulating film on the base body.