Patent ID: 8847278
Filing Date: 2014-09-30
Classification: H01L

Abstract:
1. A semiconductor device, comprising: an active section engaged in making a main current flow and a breakdown withstanding section, engaged in breakdown voltage, disposed in an external peripheral portion surrounding the active section on one major surface of a first conductivity type semiconductor substrate, wherein the breakdown withstanding section has a ring-shaped semiconductor protrusion, with a rectangular planar pattern including a curved section in each of four corners thereof, as a guard ring, and the ring-shaped semiconductor protrusion has a second conductivity type region therein, is sandwiched between a plurality of concavities deeper than the second conductivity type region and, a difference in height between the ring-shaped semiconductor protrusion and the concavities being less than 2 μm, has an electrically conductive film across an insulator film on a surface thereof; wherein a plurality of ring-shaped semiconductor protrusions are arranged between an active section side and a chip edge side at different distances from the active section side, a plurality of electrically conductive films are formed on each of respective ones of the plurality of ring-shaped semiconductor protrusions, and edges of the plurality of electrically conductive films are positioned closer to the active section side as a distance between a corresponding ring-shaped semiconductor protrusion and the active section side increases.