US Patent 7633123 Semiconductor device having super junction structure

A semiconductor device includes: two main electrodes; multiple first regions; and multiple second regions. The first region having a first impurity concentration and a first width and the second region having a second impurity concentration and a second width are alternately repeated. A product of the first impurity concentration and the first width is equal to a product of the second impurity concentration and the second width. The first width is equal to or smaller than 4.5 μm. The first impurity concentration is lower than a predetermined concentration satisfying a RESURF condition. A ratio between on-state resistances of the device at 27° C. and at 150° C. is smaller than 1.8.