| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a superjunction semiconductor device improving an avalanche resistance in a device peripheral part to improve an avalanche resistance of the device as a whole. <P>SOLUTION: In a semiconductor device, a drain drift part 22 has a first parallel pn structure constituted of a first n-type region 22a and a first p-type region 22b by bonding alternately and repeatedly at a pitch P1. A surrounding area of the drain drift part 22 is a device peripheral part 30 consisting of a second parallel pn structure. The device peripheral part 30 is constituted of a second n-type region 30a and a second p-type region 30b by bonding alternately and repeatedly at the pitch P1 so as to be continued from the first parallel pn structure. Impurity concentration of the first and second parallel pn structures are substantially the same as each other. A third parallel pn structure formed on a surface region of the device peripheral part 30 is constituted of a third n-type region 34a and a third p-type region 34b having an impurity concentration higher than that of the third n-type region 34a by bonding alternately and repeatedly at a pitch P2 smaller than the pitch P1. An impurity concentration of the third parallel pn structure is lower than those of the first and second parallel pn structures. <P>COPYRIGHT: (C)2012,JPO&INPIT</p> |
