Silicon carbide semiconductor device

A silicon carbide semiconductor device comprising:

• a silicon carbide semiconductor layer of a first conductivity type;
• a field insulating film formed on a surface of said silicon carbide semiconductor layer;
• a Schottky electrode formed on the surface of said silicon carbide semiconductor layer on an inner periphery side relative to said field insulating film, a peripheral edge of said Schottky electrode being formed to overlap onto said field insulating film;
• a front-surface electrode that covers said Schottky electrode and extends on said field insulating film beyond the peripheral edge of said Schottky electrode;
• a terminal well region of a second conductivity type that is formed to be in contact with a part of said Schottky electrode in an upper part of said silicon carbide semiconductor layer and extends in said silicon carbide semiconductor layer on an outer periphery side relative to a peripheral edge of said front-surface electrode;
• and
• a high-concentration terminal well region of the second conductivity type that is formed in said terminal well region and has a second-conductivity-type impurity concentration higher than that of said terminal well region,
• wherein the peripheral edge of said front-surface electrode is located at a distance of 2 μm or more inward from a peripheral edge of said high-concentration terminal well region.

A silicon carbide semiconductor device comprising:

• a silicon carbide semiconductor layer of a first conductivity type;
• a field insulating film formed on a part of a surface of said silicon carbide semiconductor layer;
• a Schottky electrode formed on a part of the surface of said silicon carbide semiconductor layer on an inner periphery side relative to said field insulating film, a peripheral edge of said Schottky electrode being formed to overlap onto said field insulating film;
• a front-surface electrode that covers said Schottky electrode and extends on said field insulating film beyond the peripheral edge of said Schottky electrode;
• a terminal well region of a second conductivity type that is formed to be in contact with a part of said Schottky electrode in an upper part of said silicon carbide semiconductor layer and extends in said silicon carbide semiconductor layer on an outer periphery side relative to a peripheral edge of said front-surface electrode;
• and
• a high-concentration terminal well region of the second conductivity type that is formed in said terminal well region and has a second-conductivity-type impurity concentration higher than that of said terminal well region,
• wherein a second-conductivity-type impurity amount contained in said high-concentration terminal well region per unit area is 2.0×1014/cm2 or more.