Patent ID: 9406666
Filing Date: 2016-08-02
CPC Classification: H01L

Claim Text:
1. A semiconductor device, comprising: a semiconductor substrate of a first conductivity type; a semiconductor element that is provided on the semiconductor substrate and that includes an active region in which a main current flows and a termination structure region which surrounds the active region; a protective diode that is provided above the termination structure region, with an insulating film interposed there between, and that includes a plurality of diodes which are formed by alternately arranging first-conductivity-type semiconductor layers and second-conductivity-type semiconductor layers so as to be adjacent to each other in a direction from the active region to a peripheral region of the semiconductor substrate, one end of the protective diode being electrically connected to a high-potential electrode which is provided on an outer circumferential side of the semiconductor element, and another end of the protective diode being electrically connected to a gate wire of the semiconductor element which is provided on the active region side; at least one diffusion layer of a second conductivity type that is selectively provided in a surface layer of a surface of the semiconductor substrate, which comes into contact with the insulating film, so as to surround the active region in the termination structure region, an outermost diffusion layer of the at least one diffusion layer having an outer circumferential end outside of which said one end of the protective diode is disposed; and a surface protective film that covers the termination structure region, wherein the termination structure region is divided into a first section in which the protective diode is arranged, a second section which has a width that is smaller than that of the first section, and a third section that connects the first section and the second section, and that has a width that decreases from the first section toward the second section, and wherein the at least one diffusion layer has a ring shape in a plan view which includes a first portion that is arranged in the first section and faces the protective diode in a depth direction, a second portion that is arranged in the second section, that is disposed closer to the outer circumference of the semiconductor substrate than the first portion, and that has a surface area that is greater than that of the first portion, and a third portion that is arranged in the third section.