Semiconductor Device Including Trench Structure and Manufacturing Method

A semiconductor device, comprising:

• a silicon carbide semiconductor body comprising a source region of a first conductivity type and a body region of a second conductivity type;
• a trench structure extending from a first surface into the silicon carbide semiconductor body along a vertical direction, the trench structure comprising a gate electrode and a gate dielectric,
• wherein the trench structure is stripe-shaped and runs along a longitudinal direction that is perpendicular to the vertical direction,
• wherein the source region comprises a first source sub-region and a second source sub-region alternately arranged along the longitudinal direction,
• wherein a doping concentration profile of the first source sub-region along the vertical direction differs from a doping concentration profile of the second source sub-region along the vertical direction.

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

• forming a source region of a first conductivity type and a body region of a second conductivity type in a silicon carbide semiconductor body;
• forming a trench structure extending from a first surface into the silicon carbide semiconductor body along a vertical direction, the trench structure comprising a gate electrode and a gate dielectric;
• and
• forming a contact electrically connected to the source region at the first surface,
• wherein the source region comprises a first source sub-region directly adjoining the contact at a source contact area of the first surface, a second source sub-region, and a third source sub-region,
• wherein the second source sub-region is arranged between the first source sub-region and the third source sub-region along the vertical direction,
• wherein a doping concentration profile along the vertical direction of the source region includes a doping concentration minimum in the second source sub-region and a doping concentration maximum in the third source sub-region,
• wherein each of the second source sub-region and the third source sub-region overlaps with the source contact area.

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

• forming a source region of a first conductivity type and a body region of a second conductivity type in a silicon carbide semiconductor body;
• and
• forming a trench structure extending from a first surface into the silicon carbide semiconductor body along a vertical direction, the trench structure comprising a gate electrode and a gate dielectric,
• wherein the trench structure is stripe-shaped and runs along a longitudinal direction that is perpendicular to the vertical direction,
• wherein the source region comprises a first source sub-region and a second source sub-region alternately arranged along the longitudinal direction,
• wherein a doping concentration profile of the first source sub-region along a vertical direction differs from a doping concentration profile of the second source sub-region along the vertical direction.