Semiconductor device and method for manufacturing same

A method for manufacturing a semiconductor device comprising the steps of:

• preparing a substrate made of silicon carbide and having a main surface;
• forming an active region in said substrate;
• forming a first trench having an opening at a side of said main surface of said substrate;
• forming a second trench having an opening at the side of said main surface of said substrate and shallower than said first trench;
• disposing a gate insulating film on and in contact with a wall surface of said first trench;
• disposing a gate electrode on and in contact with said gate insulating film;
• and
• disposing a contact electrode on and in contact with a wall surface of said second trench,
• in the step of forming said active region, a source region, a body region, and a drift region being formed, said source region including said main surface of said substrate, said body region making contact with said source region, said drift region making contact with said body region,
• in the step of forming said first trench, said first trench having said wall surface being formed to extend through said source region and said body region, reach said drift region, and expose said source region, said body region, and said drift region,
• in the step of forming said second trench, said second trench being formed to extend through said source region and reach said body region.