SILICON CARBIDE SEMICONDUCTOR DEVICE AND METHOD FOR MANUFACTURING THE SAME

摘要

A SiC semiconductor device includes: a semiconductor switching element having: a substrate (1), a drift layer (2) and a base region (3) stacked in this order; a source region (4) and a contact region (5) in the base region (3); a trench (6) extending from a surface of the source region (4) to penetrate the base region (3); a gate electrode (9) on a gate insulating film (8) in the trench (6); a source electrode (11) electrically coupled with the source region (4) and the base region (3); a drain electrode (13) on a back side of the substrate (1); and multiple deep layers (10) in an upper portion of the drift layer (2) deeper than the trench (6) and extending in a direction, which crosses the longitudinal direction of the trench. Each deep layer (10) has upper and lower portions (10b, 10a). A width of the upper portion (10b) is smaller than the lower portion (10a).