Silicon carbide semiconductor device and method of manufacturing the same

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

• forming a base region of a second conductivity-type including silicon carbide on a top surface side of a drift layer of a first conductivity-type including silicon carbide;
• forming a source contact region of the first conductivity-type including silicon carbide having a 3C-structure on a top surface side of the base region;
• forming a gate trench so as to penetrate the source contact region and the base region;
• depositing a gate electrode inside the gate trench with a gate insulating film interposed;
• forming a contact trench separately from the gate trench so as to penetrate the source contact region;
• depositing a main electrode inside the contact trench so as to be in contact with at least a side surface of the source contact region;
• and
• forming a base contact region of the second conductivity-type including silicon carbide having a 4H-structure and having a higher impurity concentration than the base region so as to be in contact with a bottom surface of the contact trench,
• wherein the contact trench is formed to have the bottom surface located at a position deeper than a bottom surface of the source contact region.