Silicon Carbide Semiconductor Device with Trench Gate Structure and Vertical PN Junction Between Body Region and Drift Structure

A semiconductor device, comprising:

• trench gate structures extending from a first surface into a semiconductor body of silicon carbide and spaced apart from one another along a first horizontal direction;
• a body region with a longitudinal axis parallel to the first horizontal direction, wherein the trench gate structures extend into the body region and wherein first sections of first pn junctions between the body region and a drift structure are tilted to the first surface and parallel to the first horizontal direction and wherein a vertical extension of the body region is greater than a vertical extension of the trench gate structures;
• and
• a channel blocking structure at a bottom of the trench gate structures, the channel blocking structure being configured to suppress formation of an inversion channel in a portion of the body region along a bottom surface of the trench gate structures within a maximum operating range of a gate voltage of the semiconductor device.

A semiconductor device, comprising:

• a drift structure comprising a drift zone at a distance to a first surface of a semiconductor body comprising silicon carbide and a current spread region between the first surface and the drift zone;
• a body region with a longitudinal axis parallel to a first horizontal direction, wherein along a second horizontal direction orthogonal to the first horizontal direction the body region is formed between the current spread region and a source region;
• trench gate structure extending into the body region;
• and
• a source contact structure extending into the semiconductor body and adjoining the source region.

A method of manufacturing semiconductor devices, the method comprising:

• forming source regions of a first conductivity type in a semiconductor substrate comprising silicon carbide, wherein dopants are introduced selectively through first segments of first mask openings in a first dopant mask and wherein a longitudinal axis of the first mask opening extends into a first horizontal direction;
• forming pinning regions of a complementary second conductivity type, wherein dopants are selectively introduced through second segments of the first mask openings and wherein the first and second segments alternate along the first horizontal direction;
• and
• forming body regions of the second conductivity type, wherein dopants are selectively introduced through second mask openings in a second dopant mask, wherein a width of the second mask openings along a second horizontal direction orthogonal to the first horizontal direction is greater than a width of the first mask openings,
• wherein forming the first dopant mask comprises modifying the second dopant mask or forming the second dopant mask comprises modifying the first dopant mask.