SEMICONDUCTOR DEVICE AND METHOD FOR MANUFACTURING SAME

摘要

A semiconductor device is provided with a silicon carbide layer (2) disposed on a main surface of a substrate (1), a trench (12) having a bottom surface and side surfaces disposed in the silicon carbide layer (2), an insulating film (11) disposed on the bottom surface and side surfaces of the trench, and a conductor layer (8) insulated from the silicon carbide layer (2) by the insulating film (11). The conductor layer (8) is constituted of silicon. The insulating film (11) has a first insulating layer (6) disposed on the bottom surface and side surfaces of the trench (12) and a second insulating layer (7), constituted of silicon, disposed between the part of the first insulating layer (6) positioned on the bottom surface of the trench (12) and the conductor layer (8). The second insulating layer (7) is in contact with the conductor layer (8), and the insulating film (11) thickness on the bottom surface of the trench (12) is three times or greater than that on the side surfaces of the trench (12).