Patent ID: 8431991

Claim:
A semiconductor device produced from a semiconductor material having a wider bandgap than that of silicon, the semiconductor device comprising: an active region portion in which an electric current flows; and a peripheral voltage withstanding structure portion surrounding the outside of the active region portion; wherein the peripheral voltage withstanding structure portion includes: a first semiconductor layer of a first conductivity type; a second semiconductor layer of the first conductivity type which is provided on the first semiconductor layer of the first conductivity type so that the second semiconductor layer of the first conductivity type has a higher impurity concentration than that of the first semiconductor layer of the first conductivity type; a third semiconductor layer of a second conductivity type which is provided on the second semiconductor layer of the first conductivity type; at least one trench which passes through the third semiconductor layer of the second conductivity type and the second semiconductor layer of the first conductivity type and reaches the first semiconductor layer of the first conductivity type; and an insulating film with which an inner surface of the trench is covered.