SEMICONDUCTOR DEVICE AND METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE

摘要

Disclosed is a technique which is capable of suppressing the occurrence of cracks or voids in an insulating layer within a trench. This semiconductor device (100) comprises a semiconductor substrate (10) that is provided with an element region (110) and a termination region (120) that surrounds the element region (110). The element region (110) comprises, a gate trench (20), a gate insulating film (22) that covers the inner surface of the gate trench (20), and a gate electrode (24) that is provided inside the gate insulating film (22). The termination region (120) comprises a termination trench (30) that is arranged around the element region (110), a first insulating layer (32b) that covers the inner surface of the termination trench (30), and a second insulating layer (34b) that is formed inside the first insulating layer (32b) so as to fill up the termination trench (30). The refractive index of the first insulating layer (32b) is larger than the refractive index of the second insulating layer (34b).