Patent ID: 9478621
Filing Date: 2016-10-25
CPC Classification: H01L

Claim Text:
1. A semiconductor device including a cell region and a peripheral region surrounding the cell region, the semiconductor device comprising: a semiconductor substrate including a first-conductivity-type layer, and first-conductivity-type column regions and second-conductivity-type column regions formed above the first-conductivity-type layer and serving as a drift region, the first-conductivity-type column regions and the second-conductivity-type column regions forming a super-junction structure, each of the first-conductivity-type column regions having a first-conductivity-type impurity concentration per unit volume, each of the second-conductivity-type column regions having a second-conductivity-type impurity concentration per unit volume, a part of the semiconductor substrate being included in the cell region and other part of the semiconductor substrate being included in the peripheral region; a semiconductor element disposed in the cell region; an element electrode of the semiconductor element disposed in the cell region; an outermost peripheral electrode electrically connected to the semiconductor substrate in the peripheral region; a second-conductivity-type layer formed above the super-junction structure in the peripheral region; and a potential division region formed above the second-conductivity-type layer to electrically connect the element electrode to the outermost peripheral electrode and also divide a voltage between the element electrode and the outermost peripheral electrode into a plurality of stages, a part of the potential division region overlapping the peripheral region when viewed from a thickness direction of the semiconductor substrate, wherein the peripheral region further includes a charge balance change region in which a difference between the first-conductivity-type impurity concentration and the second-conductivity-type impurity concentration of one section of the charge balance change region is larger than a difference between the first-conductivity-type impurity concentration and the second-conductivity-type impurity concentration of another section of the charge balance change region, the one section being located farther from the cell region than the another section in the peripheral region.