Silicon carbide switching device with novel overvoltage detection element for overvoltage control

摘要

A semiconductor device includes a silicon carbide semiconductor substrate, a silicon carbide layer, a switching element section, and an overvoltage detection element section whose area is smaller than that of the switching element section. The switching element section includes a first electrode pad, a first terminal section surrounding the first electrode pad and provided in the silicon carbide layer, and a first insulating film covering the first terminal section. The overvoltage detection element section includes a second electrode pad, a second terminal section surrounding the second electrode pad and provided in the silicon carbide layer, and a second insulating film covering the second terminal section and being in contact with the silicon carbide layer. A breakdown field strength of at least part of a portion of the second insulating film being in contact with the silicon carbide layer is lower than that of the first insulating film.

主权项

1. A semiconductor device comprising:
a silicon carbide semiconductor substrate; a silicon carbide layer on a principal surface of the silicon carbide semiconductor substrate; a switching element section including a portion of the silicon carbide semiconductor substrate and a portion of the silicon carbide layer; and an overvoltage detection element section including another portion of the silicon carbide semiconductor substrate and another portion of the silicon carbide layer, wherein an area of the principal surface of the silicon carbide semiconductor substrate included in the overvoltage detection element section is smaller than an area of the principal surface of the silicon carbide semiconductor substrate included in the switching element section, the switching element section includes a first electrode pad provided above the silicon carbide layer, a first terminal section surrounding the first electrode pad and provided in the silicon carbide layer, and a first insulating film covering the first terminal section and being in contact with the silicon carbide layer, the overvoltage detection element section includes a second electrode pad provided above the silicon carbide layer, a second terminal section surrounding the second electrode pad and provided in the silicon carbide layer, and a second insulating film covering the second terminal section and being in contact with the silicon carbide layer, and a breakdown field strength of at least part of a portion of the second insulating film being in contact with the silicon carbide layer is lower than that of the first insulating film.