Patent ID: 7335949

Claim:
A semiconductor device comprising: a first-conductivity-type substrate which includes an element-forming region having a gate electrode formed therein, and a peripheral region formed in the outer periphery of said element-forming region and having an element-isolating region formed therein; a field electrode formed on said peripheral region; and a parallel pn layer having a first-conductivity-type drift region, which is formed on the main surface of said substrate, and second-conductivity-type column regions dispersed in said first-conductivity-type drift region, said parallel pn layer extending oversaid element-forming region and a part of said peripheral region, in said peripheral region, at least one of said column regions, formed on an outer portion as viewed from an edge of the field electrode on said element-forming region side, being formed with a depth larger than or equal to that of said column regions formed in said element-forming region, and said field electrode being not formed just above said at least one of said column regions formed with a depth larger than or equal to that of said column regions formed in said element-forming region, wherein said field electrode has a plurality of openings which open respectively on said plurality of column regions, and are formed in an island-like manner.