Semiconductor device

A semiconductor device having an active region and a non-active region surrounding the outer periphery of the active region, the semiconductor device comprising:

• a first semiconductor layer having a first conductivity type and extending in a plane direction;
• a second semiconductor layer formed on the first semiconductor layer and having a second conductivity type different from the first conductivity type;
• and
• a third semiconductor layer formed on the second semiconductor layer and having the first conductivity type,
• the first semiconductor layer, the second semiconductor layer, and the third semiconductor layer being made of a wide band-gap semiconductor,
• in the active region, the semiconductor device comprising a trench, a first insulating film, a control electrode, and a contact electrode,
• the trench penetrating the third semiconductor layer and the second semiconductor layer to reach the first semiconductor layer,
• the first insulating film covering the surface of the trench,
• the control electrode being formed in the trench covered by the first insulating film,
• the contact electrode contacting the third semiconductor layer,
• in the non-active region, the semiconductor device comprising an outer trench, a second insulating film, a conductor, and an outer electrode,
• the outer trench penetrating the third semiconductor layer and the second semiconductor layer to reach the first semiconductor layer, and surrounding the active region,
• the second insulating film covering the surface of the outer trench,
• the conductor being formed in the outer trench covered by the second insulating film and electrically insulated from the control electrode and the contact electrode,
• the outer electrode being located outside the outer trench, contacting the second semiconductor layer, and being electrically connected to the contact electrode.